- Meat Allergy
- Managing a severe food reaction with epinephrine
- Managing Food Allergies in Children
- Mammalian meat allergy
- Who gets MMA?
- Tests and diagnosis
- What meat and other products do I have to avoid?
- Can I eat chicken and meat from other birds if I have mammalian meat allergy?
- How to protect yourself from MMA
- Killing and removing a tick
- Tick Allergy
- Ticks and health problems
- The life of ticks
- Allergic reactions to ticks
- First aid for tick bites
- What to do if you find a tick lodged in your skin and you are ALLERGIC to tick bites
- Confirming a diagnosis of tick allergy
- Tick bites and mammalian meat allergy
- Measures to reduce the risk of tick bites
- Dermatologists Will Increasingly Meet Mammalian Meat Allergy
- Alpha-Gal (Mammalian Meat) Allergy: Implications for Pharmacists
- Mammalian Meat Allergies: The Alpha-Gal Syndrome
- The Lone Star Tick
- Signs & Symptoms
- Mammalian meat allergy following a tick bite: a case report
Once a meat allergy is diagnosed, the best treatment is to avoid the trigger. Carefully check ingredient labels of food products and learn whether what you need to avoid is known by other names.
Be extra careful when you eat out. Waiters, and sometimes the kitchen staff, may not always know the ingredients of every dish on the menu.
Anyone with a food allergy must make some changes in what they eat. Your allergist can direct you to helpful resources, including special cookbooks, patient support groups, and registered dietitians who can help you plan meals.
Managing a severe food reaction with epinephrine
A food allergy, including a meat allergy, can cause symptoms that range from mild to life-threatening; the severity of each reaction is unpredictable. People who have previously experienced only mild symptoms may suddenly experience a more severe reaction, including anaphylaxis. In the US, food allergy is the leading cause of anaphylaxis outside the hospital setting.
Epinephrine is the first-line treatment for anaphylaxis, which results when exposure to an allergen triggers a flood of chemicals that can send your body potentially into shock if not treated promptly. Anaphylaxis can occur within seconds or minutes, can worsen quickly, and can be deadly.
Once you’ve been diagnosed with a food allergy, your allergist will ly prescribe an epinephrine auto-injector and teach you how to use it. Check the expiration date of your auto-injector, note the expiration date on your calendar, and ask your pharmacy about reminder services for prescription renewals.
If possible, have two epinephrine auto-injectors available, especially if you are going to be far from emergency care, as the severe reaction may reoccur.
Epinephrine should be used immediately if you experience severe symptoms such as shortness of breath, repetitive coughing, generalized hives, tightness in your throat, trouble breathing or swallowing, or a combination of symptoms from different body areas such as hives, rashes, or swelling on the skin coupled with vomiting, diarrhea, or abdominal pain.
Even if you are uncertain whether a reaction calls for epinephrine, you should use it, as the benefits of epinephrine far outweigh the risk.
Common side effects of epinephrine may include anxiety, restlessness, dizziness, and shakiness. If you have certain pre-existing conditions, you may be at a higher risk for adverse effects with epinephrine.
Your allergist will provide you with a written emergency treatment plan that outlines which medications should be given and when.
Once epinephrine has been administered, immediately call 911 and inform the dispatcher that epinephrine was given.
Other medications may be prescribed to treat symptoms of a food allergy, including antihistamines and albuterol, but it is important to note that there is no substitute for epinephrine: It is the only medication that can reverse the life-threatening symptoms of anaphylaxis. These other medications can be given after using epinephrine, and antihistamines alone may be given for milder allergic reactions per your food allergy action plan.
Managing Food Allergies in Children
Because fatal and near-fatal food allergy reactions, other food allergy symptoms, can develop when a child is not with his or her family, make sure your child’s school, daycare, or other program has a written emergency action plan with instructions on preventing, recognizing, and managing these episodes in class and during activities such as sporting events and field trips.
If your child has been prescribed an auto-injector, be sure that you and those responsible for supervising your child understand how to use it. See an allergist for expert care and relief from meat allergy.
This page was reviewed and updated 5/8/2019.
Mammalian meat allergy
Mammalian meat allergy or MMA is an allergy to meat, and sometimes also to other animal products such as dairy and gelatine, caused by being sensitised earlier by tick bites. Australia has the highest prevalence of MMA in the world.
Who gets MMA?
MMA is an emerging diagnosis up and down the East coast of Australia, the prime habitat of ticks in Australia.
The paralysis tick (Ixodes holocyclus) is the tick species that is responsible for hypersensitivity reactions, such as tick allergy, in Australia, so doctors suspect that paralysis ticks are also responsible for MMA. Paralysis ticks are the most common type of tick on the East coast.
To develop MMA, a person must have first been bitten by a tick. Not everyone who is bitten by a tick will go on to develop MMA, but those who suffer large (greater than 50 mm) itchy skin reactions that may last several days, sometimes with swelling, seem most ly to develop MMA.
People who develop mammalian meat allergy after being bitten by a tick usually do so months after the tick bite.
The symptoms of mammalian meat allergy usually start 3-6 hours after eating the meat or meat product, but can be between 2-10 hours after, sometimes waking a person in the middle of the night.
This can make it difficult to link the 2 events, un other food allergies which occur soon after eating the food.
The delay is because the substance causing the allergy (alpha gal) has to be released from the meat by digestion.
The symptoms of MMA are often severe and includes symptoms of anaphylaxis in up to 60% of cases, which can be life-threatening.
Some of the symptoms that may be experienced are:
- Delayed stomach pain.
- Hives (an itchy raised skin rash doctors call urticaria).
- Difficulty breathing, shortness of breath, wheezing.
- Constriction of the throat.
- Tongue swelling.
Get urgent medical help if you start to suffer symptoms of mammalian meat allergy. Symptoms may worsen rapidly and can be life-threatening.
MMA is caused by a person becoming allergic to a sugar molecule called alpha galactose (shortened to alpha gal), which is present in the meat from most mammals.
A tick seems to acquire alpha gal in its gut or possibly saliva after feeding on a mammal, for example native mammals such as a bandicoot. All stages of ticks (except adult males) need to feed on mammals (including humans) to obtain a blood meal.
It has been suggested that the tick transfers alpha gal into a human when it regurgitates the earlier blood meal into the human, especially if it is squeezed or agitated during removal attempts, but doctors don’t seem entirely sure yet how exactly humans develop the mammalian meat allergy from the tick bite.
To avoid MMA (and other tick related illnesses) doctors now advise people who don’t have tick allergy to kill an attached tick with a freezing spray, so that it doesn’t inject you with its saliva or gut contents. Removing it with tweezers is more ly to result in the tick injecting you with saliva or its contents. See Tick removal.
Tests and diagnosis
There are some blood allergy tests that seem to be positive in most people with mammalian meat allergy. These blood tests can help confirm a diagnosis of MMA.
Your General Practitioner should be able to refer you to an allergy specialist or clinical immunologist who will be able to confirm the diagnosis if that is the case.
Un some other allergies, there is no desensitisation or allergen immunotherapy available for mammalian meat allergy or tick bite allergy at present.
Treatment of mammalian meat allergy involves total avoidance of meat from mammals. People who also react to gelatine and dairy need to avoid foods and products containing gelatin or dairy as well. This includes some medical products.
A dietitian with experience in MMA will be able to help you design a balanced diet that keeps you safe. It is especially important to get expert advice if you have gelatine or dairy allergy – the dietitian will be able to help you identify hidden sources of these products and help you find alternatives.
If you develop symptoms of mammalian meat allergy, get medical help immediately. Symptoms may get worse quickly and can become life-threatening.
What meat and other products do I have to avoid?
If you have been diagnosed with MMA, you will need to avoid eating beef, ox, lamb, pork, bacon, ham, venison, deer, veal, goat, buffalo, rabbit and kangaroo and some other meats..
Also off the menu are all sausages – even chicken ones (because the casings are made from beef products) and deli meats, such as salami and offal (e.g. tripe, kidneys and liver).
If you are one of the 10 per cent of people with MMA who are also allergic to gelatine, other meat products, or dairy, you will also need to avoid stock cubes, liquid stocks, Bovril, some confectionery (e.g. marshmallows and Jubes), jelly, jam, potato chips, mammalian milks, yoghurt, cheese and ice cream among other things.
You will also need to avoid some medicines, vitamins and medical products, which have been made with animal products. It is best to consult an allergy specialist and a dietitian experienced in MMA regarding what is safe to eat or use.
Doctors advise that you should wear a medical bracelet warning of your allergy and potentially of allergy to intravenous gelatin colloid – a product used as a blood substitute. People with MMA may also be allergic to cetuximab – a product sometimes used in chemotherapy.
Can I eat chicken and meat from other birds if I have mammalian meat allergy?
People with MMA can normally safely eat chicken, turkey, duck and quail and also fish, shellfish and molluscs, according to tiara (Tick induced allergies and awareness).
How to protect yourself from MMA
You can protect yourself from MMA by avoiding being bitten by a tick – and if you do get an attached tick, by killing it then removing it according to the latest advice (see below).
Take precautions to protect yourself from tick bites.
If you live in a tick-endemic area of Australia, don’t scratch anything you can’t see – it may be a tick and if you disturb it, it will ly inject its saliva into you.
Killing and removing a tick
Australian experts and bodies such as ASCIA (the Australasian Society of Clinical Immunology and Allergy) recommend that if you are not allergic to ticks you ‘freeze’ an adult tick with a product such as Wart-Off Freeze or Elastoplast Cold Spray.
These sprays contain ether which freezes the tick, thus immediately killing it and preventing it from injecting its saliva into you. You should then leave the tick in place until it drops off, which it should do in the next 24 hours. These sprays are available from pharmacies in Australia.
If you are allergic to tick bites, you should follow your allergy plan or your doctor’s advice.
Tick removal techniques which use tweezers or special hook- tools run the risk of the tick injecting its saliva or gut contents into you if it is squeezed or agitated/disturbed. This could expose you to transmissible diseases from the tick, sensitise you to ticks or meat, or If you suffer from tick allergy, risk you having a severe allergic reaction.
ASCIA specifically advises against using tweezers or forceps, because of the risk of people allergic to tick bites having an anaphylactic reaction.
For larval and nymph stage ticks, which are around 1-2 mm and hard to see, experts recommend applying a cream containing permethrin, such as Lyclear. These creams are available from the pharmacy.
1. ASCIA. Tick allergy. Updated June 2016. https://www.allergy.org.au/patients/insect-allergy-bites-and-stings/tick-allergy (accessed Feb 2017).2. Sheryl Van Nunen. Tick anaphylaxis and allergies. Australian Doctor 2015: 3 February: 3. Tiara (Tick induced allergies and awareness). Chefs card and MMA allergen card. http://www.tiara.org.
au/wp-content/uploads/2016/12/TiARA-MMA-card-1.pdf (accessed Feb 2017).4. Van Nunen SA et al. An association between tick bite reactions and red meat allergy in humans. Med J Aust 2009; 190 (9): 510-511.
5. Van Nunen S. Tick-induced allergies: mammalian meat allergy, tick anaphylaxis and their significance. Asia Pacific Allergy 2015: 5: 3-16.
ASCIA PCC Tick allergy 2019154.26 KB
Allergic reactions to ticks range from mild, with swelling and inflammation (at the site of a tick bite), to severe (anaphylaxis).
To prevent allergic reactions to ticks it is important that ticks are not forcibly removed or touched.
Disturbing a tick may cause more allergen-containing saliva to be injected by the tick.
Published studies show that the safest way to remove a tick is to:
- Freeze the tick, using a product that rapidly freezes and kills the tick, and allow it to drop off; OR
- Leave the tick in place and seek medical assistance to remove the tick.
Ticks and health problems
Health problems linked with tick bites include:
- Allergic reactions.
- Allergic reactions to red meat and gelatin (mammalian meat allergy).
- Transmission of infections (these are less common than allergic reactions).
- Tick paralysis (this is rare in humans as a tick must be attached for several days to inject enough toxin).
The life of ticks
Ticks are arachnids (related to spiders) and have eight legs. Tick larvae are very small, around 1mm in size and can be hard to see. Nymphs are slightly larger at around 2mm diameter, and adult ticks (before a blood feed), are around 4mm in size.
Adult ticks attach to the tips of grass blades and vegetation, and from there transfer themselves to a host which is usually a passing animal or human. The tick attaches to their host by biting the skin.
Ticks generally lodge in the skin of the head, scalp or neck of their host. The most common reaction is local irritation, itching and swelling at the site of a tick bite, which is usually not due to allergy.
Ticks are present mainly on the east coast of Australia, however, there are also populations of ticks in several non-coastal areas.
The tick season is often considered to range from July to December, when adult ticks are more prevalent, but the risk of exposure to ticks exists throughout the year.
Allergic reactions to ticks
Mild allergic reactions to ticks appear as large local swelling and inflammation at the site of a tick bite, that can last for several days.
Severe allergic reactions (anaphylaxis) to the Australian paralysis tick, Ixodes holocyclus have been reported. Anaphylaxis occurs when the tick is disturbed, as this causes the tick to inject more allergen-containing saliva.
It is important to avoid disturbing the tick by scratching something that can’t be seen, trying to remove the tick, or applying chemicals such as methylated spirits or kerosene to the tick.
First aid for tick bites
- Freeze the tick, using a product that rapidly freezes and kills the tick, and allow it to drop off. In most cases ether-containing sprays will kill the tick within five minutes, and it will drop off the skin. Published studies show that safe and fast removal of the tick may reduce the possibility of becoming allergic to ticks. It may also reduce the risk of getting a tick-borne infectious disease, or developing tick paralysis.
- If the tick does not drop off, or you can’t freeze the tick, leave the tick in place and seek urgent medical assistance to remove the tick.
- Do not scratch anything you can’t see if you live or work in a tick-endemic area.
- Know how to manage allergic reactions (including anaphylaxis) to tick bites.
It is unsafe to insert fine tweezers between the skin and the tick mouthpiece and lever the tick out. This does not prevent tick allergy or anaphylaxis, and therefore ASCIA advises against this method.
What to do if you find a tick lodged in your skin and you are ALLERGIC to tick bites
If a person is allergic to ticks, they should carry an adrenaline (epinephrine) autoinjector (such as EpiPen) and a mobile telephone. Symptoms of a severe allergic reaction (anaphylaxis) include any acute onset illness with skin reactions such as swellings, and difficulty breathing.
- If a person is having symptoms of anaphylaxis as a reaction to a tick bite, use an adrenaline autoinjector, and follow the ASCIA Action Plan.
- Do not forcibly remove the tick.
- In a tick allergic person, the tick should be killed and removed in a hospital emergency department. After consultation with a medical specialist a person with tick allergy may be able to kill and remove the tick safely without going to hospital. Some people with tick allergy are so highly allergic that medical support should always be sought. A medical specialist will advise as to which approach will be safest.
- If available, liquid nitrogen applied by a doctor is effective in killing a tick.
- If killing the tick and removing it can be safely performed by the person with tick allergy, kill the tick first by using a product to rapidly freeze the tick, to prevent it from injecting more allergen containing saliva. If the tick does not drop off, or you can’t freeze the tick, leave the tick in place and seek urgent medical assistance to remove the tick.
It is important to note that:
- This advice is the clinical experience and published studies of medical specialists who treat patients with tick allergy.
- Tick allergy should be confirmed by a clinical immunology/allergy specialist.
- There is a link between tick allergy and the development of allergic reactions to mammalian meats and/or mammalian meat-derived gelatin.
Confirming a diagnosis of tick allergy
At this time, there is no reliable skin test or blood test for allergen specific Immunoglobulin E (IgE) antibodies to confirm a diagnosis of tick allergy. Australian researchers have identified that the allergens that cause problems are proteins in tick saliva. Diagnosis is currently the history of the reaction.
Researchers have identified that the following blood allergy tests are positive in the majority of people with serious allergic reactions to tick bites. The following blood tests for allergen specific IgE may assist in confirming a diagnosis:
- Mammalian meats Immunocap.
- Alpha-galactose Immunocap. Alpha-galactose is a sugar molecule present in meat from mammals other than humans, great apes and Old World monkeys. It is also found in the gut of ticks.
- Blood tests for mast cell Tryptase may also be useful. Tryptase is an enzyme that is increased in people with a condition called mastocytosis. It is associated with a higher risk of allergic reactions to many allergic triggers including insect stings and tick bites. People with higher tryptase levels may have more severe anaphylactic reactions to insect stings and bites.
Tick bites and mammalian meat allergy
Australian allergic diseases physicians were the first to describe a link between tick bites and the development of mammalian meat allergy. These findings have since been confirmed by researchers in the USA and in Europe.
Some people will also be allergic to mammalian milks and animal-derived gelatin which is present in many food products, as a binding agent in some medications and in intravenous blood substitutes known as gelatin colloid (such as Haemaccel and Gelofusine). The target allergen associated with these allergic reactions is present in the gut of ticks, and all mammalian meats (such as beef, pork, lamb, kangaroo, and venison).
People with allergic reactions to mammalian meats are advised to avoid all mammalian meats (beef, lamb/mutton, pork, goat, horse, kangaroo, venison and other exotic mammals). Artificial blood (made from beef) and all forms of gelatin should also be avoided.
People with mammalian meat allergy should wear a medical bracelet warning of allergy to intravenous gelatin colloid. This is an intravenous preparation used as a blood substitute in emergency situations.
Measures to reduce the risk of tick bites
The following measures may reduce the risk of tick bites:
- Wear long-sleeved shirts and long trousers when walking in areas where ticks live.
- Tuck shirt into trousers.
- Tuck trouser legs into long socks.
- Wear a wide-brimmed hat.
- Wear light-coloured clothes, which makes it easier to see ticks.
- Brush clothing before coming inside to remove ticks.
- Undress and check for ticks daily, checking carefully in the neck and scalp.
- An insect repellent that contains DEET (such as RID, Tropical RID, Tropical Aerogard, or Bushmans).
- Consider using permethrin-treated clothing when exposed to tick habitat or gardening in tick endemic areas.
- People with recurrent dangerous allergic reactions to tick bites may consider relocating to an area where ticks are not endemic.
Allergen immunotherapy (AIT) which is also known as desensitization, is currently not available to switch off tick bite allergy.
© ASCIA 2019
ASCIA is the peak professional body of clinical immunology/allergy specialists in Australia and New Zealand.
ASCIA resources are published literature and expert review, however, they are not intended to replace medical advice. The content of ASCIA resources is not influenced by any commercial organisations.
For more information go to www.allergy.org.au
To donate to immunology/allergy research go to www.allergyimmunology.org.au
Updated May 2019
Dermatologists Will Increasingly Meet Mammalian Meat Allergy
It has been a decade since Van Nunen, et al. detailed 25 patients living in a tick-endemic region of Sydney, Australia, who developed a red meat allergy following large, local reactions to tick bites.
Tick-induced mammalian meat allergy (MMA) has become an emergent allergy on six continents where humans are bitten by ticks. In each country, a major specific tick species has been implicated.
In Australia, it is Ixodes holocyclus (the Australian paralysis tick); in the U.S., it is Amblyomma americanum (the Lone Star tick).
Although prominent in the Southeast, the Lone Star tick is heading north, having established itself in Connecticut. The health implications, MMA included, are clear.
Alpha-gal (galactose-alpha-1,3-galactose) is an oligosaccharide demonstrated to be present in the gastrointestinal tract of some ticks, supporting the theory that tick bites induce the production of IgE to alpha-gal and subsequent MMA.
There seems to be a correlation between severity of tick-bite-mediated local cutaneous reaction and the development of alpha-gal antibodies. These antibodies may result in delayed anaphylaxis to mammalian meats, including beef, pork, and lamb, among others.
In general, patients have reported symptoms of generalized urticaria, angioedema, or anaphylaxis from three to six hours after ingestion of mammalian meat, which was previously tolerated.
MMA is also known as the alpha-gal syndrome. The main feature differentiating it from other IgE-mediated meat allergies is the delayed reaction.
The most plausible explanation for the delay involves the time required for processing, digestion, and transport of alpha-gal epitopes to target tissues.
According to Wilson and Platt-Mills, “The kinetics of lipid metabolism, which involves packaging into chylomicrons and transit through lymphatics and the thoracic duct before entering the bloodstream, suggests the possibility that α-Gal-containing lipids are particularly important in the delayed allergic response.” Not every person who is sensitized to alpha-gal becomes symptomatic; this could be a reflection of heterogeneity in the complexity of alpha-gal linked oligosaccharide structures.
Alpha-gal residues have been found on Fab segments of the monoclonal antibody cetuximab — an EGFR monoclonal antibody used for squamous cell carcinomas of the head and neck and in metastatic bowel cancer. When administered intravenously, potentially fatal reactions may appear rapidly. Interestingly, these patients may also demonstrate delayed anaphylaxis after ingesting mammalian meat.
The first step in managing MMA is recognizing the syndrome. The long-term prognosis is not well described. Presumably (although not proven), a strict meat-avoidance diet and tick bite prevention (clothing, DEET, etc.) will abate reactions over time.
Acute episodes may require supportive care, antihistamines, epinephrine, and steroids. Patients at risk must carry an epinephrine auto-injector. Referral to an allergist is warranted.
Skin prick testing with freshly prepared meat extract appears to be the optimal test for MMA — affected patients will demonstrate a strongly positive response. Oral food challenge is not advised because of the delayed time frame and risk of anaphylaxis.
Although desensitization has been reported in two cases of the alpha-gal syndrome, this is not recommended outside of research settings.
Point to Remember: For patients presenting with urticaria, angioedema, or anaphylaxis in tick-endemic regions, consider the diagnosis of mammalian meat allergy.
Dermatologists Will Increasingly Meet Mammalian Meat Allergy
last updated 06.19.2019
Alpha-Gal (Mammalian Meat) Allergy: Implications for Pharmacists
Alpha-Gal (Mammalian Meat) Allergy: Implications for Pharmacists
Indrani Kar, PharmD; Min Gong, PharmD candidate; Christine Muglia, MD; Catherine A. Monteleone, MD; and Evelyn R. Hermes-DeSantis, PharmD, BCPS
What Is Alpha-gal and Mammalian Meat Allergy?
Alpha-gal (galactose-alpha-1,3-galactose), a mammalian oligosaccharide, has recently been implicated in delayed anaphylaxis reactions to mammalian meat. First described in 2009, the alpha-gal allergy (red meat or mammalian allergy) is a novel form of IgE-mediated anaphylaxis; un most anaphylaxis, this reaction is delayed. Individuals with high IgE titers to alpha-gal have experienced urticaria, angioedema, and anaphylaxis symptoms 3 to 6 hours after ingesting mammalian meat (beef, pork, lamb, venison, goat, and bison), which is rich in alpha-gal.1
Many animal by-products may contain the alpha-gal epitope. Animal by-products derived from turkey, chicken, and fish, however, do not.
2 Whereas the alpha-gal epitope is also present in cat IgA, a monoclonal antibody found in cat dander, cat exposure has not been associated with allergic reactions.
However, patients with the alpha-gal allergy have shown positive skin and blood tests to cat IgA.1
The alpha-gal allergy affects both children and adults.3 The severity of the allergy and the allergy itself may recede over time.1
Evolution of Alpha-gal
Humans do not naturally produce alpha-gal epitopes, as the alpha-1,3-glycosyltransferase enzyme is inactivated in humans, old world monkeys, and apes. Other mammals, new world monkeys, placental mammals, marsupials, and prosimians, however, produce alpha-gal and the enzyme. Humans produce IgG2 anti-gal naturally, which protects them against normal bacteria flora in the gut that produces the alpha-gal epitope.4 Patients with blood group B or AB have fewer anti-gal antibodies and therefore may be less ly to develop the mammalian meat allergy (or develop a milder reaction).5 Research suggests that exposure to the alpha-gal epitope in a tick bite may cause normal anti-gal antibody formation to switch from IgG2 to the IgE involved in the delayed anaphylaxis response to the specific types of mammalian meat previously mentioned.5,6
Prevalence and Location
Experts estimates that thousands of Americans have the alpha-gal allergy,7 with a causal relationship between lone star tick bites and these anaphylactic reactions. Individuals bitten by lone star ticks can develop IgE antibodies to alpha-gal. The highest infestations of lone star ticks occur in the eastern states.8
To prevent anaphylaxis, affected patients should avoid any medication, supplements, foods, etc that may contain the alpha-gal epitope; this is their only treatment option. A comprehensive list of medications containing alpha-gal or animal by-products is unavailable at this time. Alpha-gal allergy testing is commercially available and requires a serum sample.
As previously mentioned, many animal by-products may contain the alpha-gal epitope. Gelatin, derived from beef, is one .9 Animal-derived magnesium stearate is another.
Cetuximab, a chimeric mouse–human IgG1 monoclonal antibody against epidermal growth factor receptor, contains the alpha-gal epitope in its Fab arm portion and has been known to cause the alpha-gal allergy.
11 Additional medications, inactive ingredients, and procedures are also known to contain or utilize the alpha-gal epitope such as:
- Creon 102
- Protein powders with whey2
- Xenograft surgery6
The issue with xenograft surgery has been resolved by using knock-out pigs lacking the alpha-gal epitope.4
To obtain information on animal by-product content, health care providers must contact manufacturers. Manufacturers do not currently report alpha-gal content in their package inserts or test for alpha-gal content in products.
Inactive ingredient information can change at any time, and the FDA does not require manufacturers to disseminate this information. To prevent unnecessary exposure to alpha-gal, pharmacists should ensure that alpha-gal allergic patients avoid meat-containing medications.
To provide timely patient care, alpha-gal information needs to be readily available, which is an area in which pharmacists can make an impact.10
Drug Information Service Contribution
At an academic medical center, a patient with the alpha-gal allergy with allergic reactions to antihypertensive medications presented to an immunologist.12 The medications contained gelatin and magnesium stearate. The drug information service proceeded to create an alpha-gal content database to support the selection of an appropriate antihypertensive pharmacotherapy regimen for patients who have the alpha-gal allergy. Pharmacists contacted manufacturers with the broadest range of antihypertensive medications, and asked, “Do your products contain galactose-alpha-1,3-galactose, alpha-gal, mammalian meat, or any animal by-products?” No manufacturers tested for the presence of alpha-gal in their product, but animal by-product content was available. All manufacturers took more than 24 hours to respond, and some required 1 or more call-back attempts. correspondence with manufacturers, the Table lists medications that do not contain animal by-products, suggesting they are alpha-gal-free. The drug information service continues to review and add medications to its database. It has reviewed hyperlipidemia medications, narcotics, and dermatologic creams to date.
Table: Medications that Do Not Contain Animal By-products (per the manufacturer)
|Losartan potassium tablet, film coated||Sandoz|
Although alpha-gal content cannot be completely ruled out, products without animal by-products theoretically may be used to safely treat patients with a documented alpha-gal allergy. One limitation of this database is that manufacturers do not routinely test for alpha-gal, so definitive conclusions cannot be drawn. However, the lack of information is intrinsic to the subject matter and not a database flaw.
The rising incidence and the serious nature of the alpha-gal allergy underscores the importance of properly managing patients. There is a need for more information on this topic.
This database simplifies the task of verifying critical information and promotes timely decision making. The flexible design also allows for expansion to offer a complete reference.
In the future, this database aims to compile all alpha-gal–related information into 1 central location for all medication classes.10
Pharmacists should be cognizant of patients presenting with anaphylaxis symptom, with a history of exposure to ticks and of consuming mammalian meats. The delay in symptom presentation may be attributed to the time required to digest meats. As pharmacists, knowing a patient’s full history will enhance recognition of the allergy.
Resources for pharmacists include the Alpha-Gal Allergy Awareness Web site (www.alpha-gal.org). The Robert Wood Johnson University Hospital drug information service database is available for use by pharmacists by calling 732-937-8842.
Additional research is required on the effect of alpha-gal in medications for patients with the alpha-gal allergy. Pharmacists, especially in the emergency department and ambulatory care settings who see patients with tick bites, should be aware of this allergy and medication’s potential to elicit symptoms. Indrani Kar, PharmD, is a drug information resident at the Ernest Mario School of Pharmacy at Rutgers University and Robert Wood Johnson University Hospital in New Brunswick, New Jersey. Min Gong is a PharmD candidate at Ernest Mario School of Pharmacy. Christine Muglia, MD, is a second-year internal medicine resident at Robert Wood Johnson Medical School.
Catherine A. Monteleone, MD, is a professor of medicine at Robert Wood Johnson Medical School. Evelyn R. Hermes-DeSantis, PharmD, BCPS, is director, Drug Information Service, and a clinical professor, at Robert Wood Johnson University Hospital, Ernest Mario School of Pharmacy.
- Commins SP, Platts-Mills TA. Delayed anaphylaxis to red meat in patients with IgE specific for galactose alpha-1,3-galactose (alpha-gal). Curr Allergy Asthma Res. 2013;13(1):72-77. doi: 10.1007/s11882-012-0315-y.
- Alpha-gal basics. Alpha-Gal Allergy Awareness website. http://alpha-gal.org. Published 2014. January 9, 2015.
Mammalian Meat Allergies: The Alpha-Gal Syndrome
The reaction is a systemic release of antibodies that binds to a carbohydrate present in mammalian meat called galactose-alpha-1,3-galactose (alpha-gal). Mammalian meat is any meat that comes from a mammal including beef, pork, lamb, venison, goat and bison.
Fish, turkey and chicken are not mammals, so they don’t have alpha-gal.
When a person with the alpha-gal antibody eats mammalian meat, the meat triggers the release of histamine, a compound found in the body that causes allergic symptoms hives, itching and even anaphylaxis.
Since the reaction to eating mammal meat is delayed by several hours, the proper diagnosis is often missed or misdiagnosed. People who are afflicted with the Alpha-Gal allergy have to be constantly vigilant about the ingredients they consume, because an allergic reaction can be severe and life-threatening.
For reasons yet unknown, researchers think the bite from a Lone Star tick exposes humans to a sugar from its gut called galactose-alpha-1,3-galactose, or “Alpha-Gal.” In some cases, the human immune system develops an allergic response to that sugar.
Because Alpha-Gal is also found in red meat, a bite by the Lone Star tick may translate to an allergic reaction to anything from beef hamburgers to bacon. Repeated tick bites can potentially cause the antibody level of Alpha-Gal to rise, worsening reactions.
People with the allergy can go into a delayed anaphylactic shock, four to six hours after eating red meat.
Alpha-gal allergy is different from other food allergies the peanut allergy as the response is delayed. Un someone with a peanut allergy who has an immediate allergic response after eating peanuts, people with the alpha-gal allergy do not start having symptoms until several hours after they eat mammalian meat. When it comes to allergies, the human immune system has a “memory”.
Proteins found in peanuts and eggs trigger the immune system much faster than the proteins found in Alpha-Gal sugar, which takes significantly longer for the immune system to recognize. There seems to be a correlation between the amount of meat eaten and the fat content of the food.
There seems to be a correlation with metabolism of the fat, which explains the red meat allergy’s delayed reaction.
The Lone Star Tick
The Lone Star (Amblyomma americanum) tick is a medium-sized, reddish-brown tick that’s common in the Southeastern United States. It gets its name from a white dot found on the backs of all female adults.
Lone Star ticks “bite” by inserting needle- mouth parts into the skin, while backward-facing teeth act as hooks, securing them in place. They also secrete a cement- substance that helps them to stay attached.
Signs & Symptoms
Signs and symptoms of a severe allergic reaction and anaphylaxis typically includes truncal hives, but may also include swelling, vomiting, diarrhea, trouble breathing and a rather significant (and quick) drop in blood pressure. Be sure to dial 9-1-1 for anyone who is having trouble breathing — especially if you suspect anaphylactic shock!
Though there is no exact indication of how long the allergy to red meat lasts, it’s possible that it may improve over time. Avoiding repeated tick bites is the key, as your antibody levels should diminish.
The obvious answer here as far as prevention of anaphylaxis (for those who have the Alpha-Gal allergy) is to stay away from red meat such as beef, pork, lamb, venison, goat and bison, and stick to a diet of chicken, seafood and turkey.
Some but not all patients need to avoid milk, cheese, and real butter.
Mammalian meat allergy following a tick bite: a case report
New York Institute of Technology College of Osteopathic Medicine at Arkansas State University, Jonesboro, AR, USA,
Find articles by W Landon Jackson
The alpha-gal allergy is an emerging IgE-mediated reaction against the galactose-alpha-1,3-galactose carbohydrate found in mammalian meats. Patients with this condition will develop anaphylactic symptoms 3–6 h after the ingestion of mammalian meat food products such as beef, pork or lamb.
The prevalence of this allergy is drastically increasing and severe reactions including anaphylactic shock have been reported, yet many patients experience symptoms for years before a diagnosis is made.
We describe the presentation, diagnosis and management of a patient with the alpha-gal allergy in attempt to improve early recognition and management of patients with this condition.
The alpha-gal allergy is a recently recognized IgE-mediated reaction against the galactose-alpha-1,3-galactose carbohydrate found in non-primate mammalian meats .
Un other food allergies, this condition elicits a delayed onset of anaphylactic symptoms 3–6 h after the ingestion of mammalian meat food products such as beef, pork or lamb.
Studies suggest that being bitten by the lone star tick (Amblyomma americanum) is the only significant cause of these responses in the United States . These ticks are common in the southeastern region of the country.
Although the prevalence of the alpha-gal allergy is drastically increasing and severe reactions leading to anaphylactic shock can occur , this condition is rarely recognized and a mean time of 7.1 years to diagnosis was found in 2017 . Delayed diagnosis of an allergy that has proven to elicit such potent reactions is exceptionally dangerous.
We report a 60-year-old male with alpha-gal allergy in attempt to improve early recognition and management of patients with this condition.
A 60-year-old Caucasian male presented to his primary care physician (PCP) with a 3-week history of daily spontaneous allergic reactions without an identifiable cause or pattern.
His symptoms included a painful and pruritic urticarial rash involving his entire body along with abdominal pain, diarrhea, congestion, cough and sore throat. The patient reported multiple episodes of waking in the middle of the night with severe pruritus that would resolve a few hours after taking Benadryl.
One reaction led to shortness of breath and constriction of the patient’s throat, so he went to the emergency department and was treated for anaphylaxis (Fig. 1).
The patient’s medical history was unremarkable with no previous diagnoses of allergies, asthma or atopy.
No specific triggers for these reactions could be identified, and the patient reported no changes in soaps, washing detergents or stress levels.
He denied consuming alcohol, but did report a diet rich in beef and dairy products. The patient also acquired a tick bite in Arkansas ~2 weeks prior to the onset of symptoms.
An urticarial rash involving the torso, upper extremity and dorsum of the hand was noted upon examination. The urticarial lesions were annular, slightly raised, various in size and blanching. The patient reported the rash would last