Alpha-gal Tolerance Levels

Everybody is Different!

The thing about Alpha-gal Syndrome is that reactions seem to be as individual as each of us is. About half of us can eat dairy, some have reactions from carrageenan, some of us react to fumes, but most don’t. And reactions can change over time. People get over fume reactions while others who may never have had them before suddenly develop them. It’s a crazy roller coaster ride, but just because we have AGS, it doesn’t define who you are. Here, you know you’re never alone, we’re stronger together and here to help. The important thing to remember is to figure out your triggers & avoid them and otherwise do the things you’d normally do as much as possible.  Jennifer Burton, Alpha Gal Encouragers of NW Arkansas

Two ways in which alpha-gal syndrome differs from typical allergies are:
1. Reactions to alpha-gal vary enormously from individual to individual.

This means:

  • Some people only have to stop eating mammalian meat and organs.
  • Other people need to avoid additional foods, like dairy and gelatin, as well.
  • Still others cannot tolerate a wide variety of foods, personal care and household products that contain only micrograms of alpha-gal.
  • Some people react to airborne particles of alpha-gal, such as those produced by cooking meat.

Mine started out as gastro issues. Bloating, cramps, diarrhea and vomiting. That was after initial tick bite. A few months later I got into chiggers and started getting full blown anaphylaxis to include those symptoms plus drop in BP, hives, swelling, passing out, anxiety.

Julie Smith LeSueur

I already had alpha-gal syndrome and could not handle beef, but I could handle dairy. I used to eat Cheez-its and Cheetos all the time. They made great movie snacks! I had no problems with dairy then, that I know of, other than inflammation. Then, I was bitten by more ticks. Less than a month later, I had anaphylaxis from a snack at work one night. Just a handful of Cheez-its caused anaphylaxis within minutes. Shortness of breath, full body hives, migraine, heart pounding, drop in blood pressure, facial flushing, hot sweats and cold chills, diarrhea, and vomiting all simultaneously.

Crystal J. Norton

2. With each individual, reactions to alpha-gal vary from exposure to exposure, and often over time.

This means:

  • You may react differently to the same foods on different occasions. For example, one day, you may tolerate milk; the next day, it may cause abdominal pain and hives.
  • If you are lucky, you may become less reactive with time, especially if you avoid additional tick bites.
  • If you are less lucky, you may become more reactive, especially if you are bitten by ticks again. For example, you may be able to tolerate everything except mammalian meat and organs. Then, one day, dairy products start to bother you, or you develop fume reactions. 

Before I was diagnosed, sometimes I would eat a hamburger and nothing would happen.
Sometimes I would eat a hamburger and just get cramps/bloating/diarrhea, occasionally vomiting.
Sometimes I would eat a hamburger and my throat would close and I would have hives the size of dinner plates.

It  was always Russian roulette. It could be the prepared exactly the same. It could be from the same cow. The only thing different is how I react to it.

Megan Thomas

This is why we need to be careful! Always carry your meds, your epinephrine autoinjectors (like EpiPens), your rescue plan, etc. You never know when you might have a bad reaction, possibly a worse one than you have experienced before!

Different Levels of Tolerance


If you are newly diagnosed, you might not know how much alpha-gal it takes to cause you to react. There are many levels of tolerance.

Virtually everyone with AGS  reacts to:


Even people who do not react when they eat mammalian meat, and are otherwise asymptomatic, but who test positive for alpha-gal IgE, will almost always react to the cancer drug cetuximab. Sometimes these reactions are fatal.

Mammalian Organs, Meat, and Other Mammalian Products including:
  • The internal organs of mammals, like liver, heart, intestines (tripe), and kidneys, which contain even more alpha-gal than meat
  • Mammalian meats, like beef, pork, lamb, bison, venison, goat, horse, rabbit, squirrel, kangaroo, antelope, buffalo, camel, guinea pig, bats, etc.
  • Other mammalian tissues, cells, and fluids, like blood
  • Meat broths
  • Meat flavorings
  • Meat extracts
  • Mammalian gut sausage casings (turkey and chicken sausages often have these)
  • Lard and suet (often in cooked foods, such as pastries, refried beans, etc.)
  • Other products containing mammalian meat or organs

About half of all people with AGS react to some dairy products, such as:

  • Milk
  • Dairy products like:
    • Cream
    • Ice cream
    • Yogurt
    • Cheese
    • Butter
    • Ghee
    • Sour cream
    • Natilla
    • Madila
    • Whey

10-30% of people with AGS react to airborne articles, including (but not exclusively):

  • Fumes from cooking meat
  • Fumes from cooking milk

Some people with AGS may react to:

Non-meat, non-dairy foods, such as  some:
  • Cross-contaminated food, like chicken cooked on the same grill as beef
  • Rennet, which is found in some cheeses and other foods
  • Products with gelatin in them, including Jello, marshmallows, gummy candies, gummy supplements
  • A wide variety of foods that contain mammalian byproducts, including many processed foods
  • Dairy byproducts, like whey and casein
  • Canned tuna, possibly contaminated with dolphin
  • Carrageenan, which is not from mammals, but contains the alpha-gal epitope
Drugs and other medical products, such as some:
  • Infliximab, pancreatic replacement enzymes, heparin, vaginal capsules, and many other perioperative and prescription medications
  • OTC medications that contain mammalian-derived ingredients, including inactive ingredients, such as gelatin capsules and magnesium stearate
  • Many medical products and devices, including (but not limited to) some bioprosthetic heart valves, antivenoms (such as CroFab), catgut sutures, topicals, adhesives, and plasma volume substitutes
  • Many vaccines with mammalian-derived ingredients, especially those with gelatin in them, such as MMR and Zostavax
Personal care products, such as some:
  • Products containing lanolin
  • Personal care products with mammalian byproducts or carrageenan in them, including some:
    • Lotions
    • Shampoos
    • Conditioners
    • Toothpaste
    • Deodorant
    • Make-up
    • Feminine care products
    • Lubricants
Household and cleaning products, such as some:
  • Air fresheners
  • Candles
  • Laundry detergents
  • Laundry sheets
  • Toilet paper
Other types of exposure, including:
  • Pet saliva and dander
  • Exposure to farm animals and their waste
  • Some people with AGS report reactions to semen when their partners have eaten mammalian meat within the 48 hours prior to sexual activity.

Determining Your Personal Level of Tolerance

Your doctor needs to advise you as to what’s safe for you, based on your clinical history, test results, and whatever other factors they deem appropriate. If your doctor thinks you might be able to tolerate some foods and other products with alpha-gal in them, then they should advise you how to determine this safely.

Step 1: Stop eating these mammalian products:
  • The internal organs of mammals, like liver, heart, intestines (tripe or offal), and kidneys, which contain even more alpha-gal than meat
  • Mammalian meats, like beef, pork, lamb, bison, venison, goat, horse, rabbit, squirrel, kangaroo, antelope, buffalo, camel, guinea pig, bats, whales, etc.
  • Other mammalian tissues, cells, and fluids, like blood, fat, nerves, brain
  • Meat broths, bouillon, stock, and gravy
  • Meat flavorings, including some “natural flavorings”
  • Meat extracts
  • Mammalian gut sausage casings (turkey and chicken sausages often have these). Removing casings is not advised, as severe reactions may still occur from cross-contamination.
  • Animal fat, like lard and suet (often in cooked foods, such as pastries, pie crusts, tortillas, refried beans, baked beans, etc.)
  • Other products containing mammalian meats or organs
  • Any other mammalian products and byproducts that you notice you react to

Do this even if your reactions are mild. Reactions to alpha-gal are extremely variable, and your next reaction could be more serious.

Step 2: Take note of any airborne reactions.

Reactions to airborne alpha-gal often start within minutes of exposure, progress quickly, and can be life-threatening. For some people with AGS, fume reactions are the most dangerous reactions that they experience, leading rapidly to anaphylaxis, airway issues, and/or unconsciousness. 

If you experience ANY airborne reactions, remove yourself immediately from the source of exposure!

People with AGS report reacting to airborne particles of alpha-gal in:
  • Suspended fat droplets in smoke or fumes from cooking meat, especially from grills, barbeques, and sometimes frying meat.
  • Fumes cooking milk or dairy products
  • Powdered dairy products, like baby formula or cheese-flavored snack items
  • Pet dander
  • Emissions from mammals and mammalian waste
  • Dryer sheets, many of which contain lanolin
  • Candles which can contain tallow or stearic acid from mammals
  • Other sources of airborne alpha-gal
Symptoms they report include (but are not limited to):
  • Itching or tingling
  • Hives, rash or flushing
  • Angioedema (swelling)
  • Nausea or other GI issues
  • A tingling throat
  • Breathing issues like coughing, wheezing, shortness of breath, airway issues
  • Dizziness
  • Changes in blood pressure or heart rate
  • Brain fog or confusion
  • A sense of impending doom
  • Lightheadedness
  • Loss of Consciousness
  • Other symptoms of anaphylaxis
Managing airborne reactions:
  • Remove yourself immediately from the source of exposure!
  • Wash your hands and face as soon as possible.
  • Seek the advice of your doctor about how to cope with future exposures, including what medications to take.
  • Work with your doctor to develop a Food Allergy and Anaphylaxis Emergency Care Plan.
  • Avoid situations where you might be exposed to airborne alpha-gal particles, such as barbecues and restaurants that grill meat.
  • For situations in which you may not be able to avoid exposure to airborne particles of alpha-gal, such as airplanes, consider buying an N99 mask. Cambridge masks are a popular brand.
  • Coming soon: Living with Airborne Reactions
Step 3: Try eliminating rennet, dairy, gelatin, and carrageenan

If you stop eating all mammalian meat and organs and continue to experience symptoms, talk to your doctor about eliminating foods and other products containing rennet, dairy, gelatin, and carrageenan. Sometimes people stop eating all these foods at once; sometimes they try giving up one category at a time, usually starting with rennet and dairy, then gelatin, and finally carrageenan. As everyone’s reactions are different, this might not be the right order for you. For example, some people react more to gelatin than to dairy.

  • Rennet is a complex set of enzymes produced in the stomachs of ruminant mammals that is sometimes used in foods, especially cheese.
  • Some people with AGS can eat dairy products, as long as they don’t contain rennet from mammals, such as calf rennet.
  • Parmesan contains mammalian rennet.
  • Some other cheeses, especially hard cheeses, also contain mammalian rennet.
  • Some packaged macaroni and cheese contains mammalian rennet.
  • Check ingredient lists on labels for rennet, but keep in mind that names of ingredients can be confusing.
  • Mammalian rennet can be listed as “enzymes” or “traditional rennet” on a cheese’s ingredient list.
  • Some rennets are derived from microbes. These may be listed as “vegetable rennet.”
  • Look for cheeses labeled “vegetarian.”
  • Rennin (also called chymosin) and lipase, which are also used to make cheese, also come from mammals.
  • Find cheeses that don’t contain rennet on the Vegetatio list of vegetarian cheeses.
  • Read Bad News: These 11 Cheeses Aren’t Always Vegetarian for a list of some, but not all, cheeses that do contain rennet.
  • See The Definitive Guide to Vegetarian Cheese for more info about both cheeses with and without rennet.
  • Is Cheese Vegetarian? is a quick guide to finding information about rennet on cheese labels.
  • Junket, a dessert more popular in previous centuries, also contains rennet.
Milk and Dairy
  • As alpha-gal seems to be concentrated in animal fat, high-fat dairy products are the most likely to trigger reactions.
  • Some people need to stop eating ice cream but can keep eating other dairy products.
  • Other high-fat dairy products that tend to be problematic include butter and ghee.
  • Some people can tolerate cheese that is not made with rennet, especially low-fat cheeses.
  • Cream contains more alpha-gal than milk, but many people who react to higher-fat dairy products tolerate both.
  • Whey protein powder, a concentrated form of milk protein, can trigger reactions in some people who tolerate other dairy products. Look for it in protein powders, protein bars, and supplements.
  • Casein is another dairy product to look out for.
  • Check labels. Milk is a Big 8 allergen and must be declared on ingredient lists.
  • See the Wikipedia list of dairy products to see which other foods are dairy products.
  • The Milk Allergy Avoidance List includes a long list of dairy products, as well as dairy byproducts.
  • Beware of ingredients in non-dairy products which may also contain alpha-gal, including whey, casein, vitamin D3 (from lanolin), and carrageenan.
  • Some people who don’t tolerate dairy products also react to dairy byproducts in foods, drugs, and other products.
  • See Guide for the Highly Reactive for more information about dairy byproducts. Coming soon!



Exposure to gelatin can be oral, as with medications in capsules and foods, or parenteral (not oral), as with vaccines and medications delivered through an IV. Here we deal ONLY with gelatin taken orally. Even people who tolerate oral gelatin, such as foods, supplements, and some medications, may experience severe and sudden-onset symptoms, including anaphylaxis, when medical products containing gelatin are injected or administered through an IV.

  • Fewer of us react to gelatin in foods than to dairy, but for some of us, our reactions to gelatin are worse than our dairy reactions.
  • Some, but not all, foods that contain gelatin include:
    • Candies, like gummy candies                             Food thickeners
    • Marshmallows                                                       Dips
    • Pastries                                                                   Glazes
    • Poptarts                                                                  Mayonnaise 
    • Icing                                                                         Sausage coatings
    • Yogurt                                                                      Soups and stock
    • Ice cream 
  • Many wines and juices are clarified with gelatin.
  • Many personal care products contain gelatin. 
  • Many medications and supplements contain gelatin, especially those in capsules. Seek the advice of your doctor about whether you should stop taking any supplements or medications.
  • For most medications, there are alternatives that do not contain mammalian-derived ingredients like gelatin.
  • Carrageenans are a family of linear sulfated polysaccharides that are extracted from red edible seaweeds. They are widely used in the food industry, for their gelling, thickening, and stabilizing properties 
  • Even though carrageenans do not come from mammals, they contain the alpha-gal linkage or epitope.
  • Scientists have not proved that the alpha-gal in carrageenan can affect people with AGS, but many of us react to carrageenans, and our reactions can be severe.
Step 4: Avoid Cross-contamination

Coming soon.

Step 5: If you have a pet, consider whether it may be causing reactions.
If you suspect that your pet may be triggering alpha-gal reactions, try the following:
  • Stop sleeping with your pet. Move your pet’s bed out of the bedroom. This is important for tick avoidance as well.
  • Don’t let your pet lick you. Pet saliva causes more people to react than pet dander.
  • If your pet does lick you, wash with soap and water right away. 
  • Pet dander can trigger airborne reactions. Take note of any airborne reactions to pet dander. 
  • If pet dander bothers you, consider buying a HEPA to put next to your pets sleeping area.
  • If you continue to react after contact with your pet, try washing your hands after you pet them.
  • Switch your pet’s food to a brand that contains fish or chicken, instead of mammal. Many people find that this helps the most.
  • Switch to vegan grooming supplies.
  • Unfortunately, some people find that they need to find new homes for their pets after they develop AGS, but this is uncommon.
Step 6: Explore the Possibility of Other Health Issues

If you stop eating rennet, dairy, gelatin, and carrageenan and still experience symptoms, talk to your doctor about the possibility that you have other health issues. Just because you have AGS does not mean that you can’t develop other conditions as well. If your symptoms cannot be explained by other health issues, you may be reactive to trace amounts of alpha-gal in mammalian-derived ingredients.

Step 7: Still Reacting? What Now?!
  • Some people with AGS react to micrograms of alpha-gal in foods, medications, personal care and household products.
  • With your doctor’s approval and guidance, try limiting your exposure to foods, medications, personal care and  household products with mammalian-derived ingredients.
  • Do not stop taking medications without your doctor’s approval.
  • See the Medications section of this website (coming soon) to learn about  how to find medications without mammalian ingredients.
  • This can be a daunting task, as there are hidden mammalian ingredients with strange names in many medications and foods.
  • Even unexpected products, like ketchup, nondairy creamers, wine and beer, lotions, toothpaste, toilet paper, and dryer sheets can contain mammalian byproducts.
  • Our Guide for the Highly Reactive (coming soon), can help you with some ideas for how to approach this.
  • Consider joining the Facebook Alpha Gal Support Nonpublic group, where there are lots of highly reactive people who can share their experiences.

 I react to the dog dander. Gives me esophageal spasms.

Amber Roberts

I go into anaphylaxis if I ingest mammal meats. I end up on the toilet for 2 days if I ingest dairy.
I end up with severe headaches and body pains if I’m ingesting medications that contain mammal. If I’m around fumes of mammal being cooked, I end up w
ith nausea, diarrhea, swollen face and hands, indigestion, headaches, red eyes that are also swollen, and severe body pains. Thankfully I only end up with red and burning skin if I touch mammal meats.

Amber Roberts

Carrageenan causes a more immediate reaction than typical for me. It causes abdominal bloating and GI issues lasting at least two days. I become very fatigued, my body becomes flushed, I get hives, and get foggy in the mind. It’s one of the worst reactions I’ve had and it’s in vegan sour cream and ice cream!

Ashley Magruder

 I already had alpha-gal syndrome and could not handle beef, but I could handle dairy. I used to eat Cheez-its and Cheetos all the time. They made great movie snacks! I had no problems with dairy then, that I know of, other than inflammation. Then, I was bitten by more ticks. Less than a month later, I had anaphylaxis from a snack at work one night. Just a handful of Cheez-its caused anaphylaxis within minutes. Shortness of breath, full body hives, migraine, heart pounding, drop in blood pressure, facial flushing, hot sweats and cold chills, diarrhea, and vomiting all simultaneously.

Crystal J. Norton

For more information about tolerance levels, read Darcie Clements excellent Adapting to AGS Part I: Understanding Tolerance Levels.