What Is a Milk Allergy?

A milk allergy is when your body negatively reacts to the proteins in animal milk. The alpha S1-casein protein in cow’s milk is the cause of most milk allergies. Therefore, milk allergies are sometimes also called a milk protein allergy or a cow milk allergy. An allergic reaction to cow’s milk is the most common allergy among children. Your child’s immune system overreacts to the milk proteins, causing an allergic reaction. Adults can also experience milk allergies, sometimes referred to as milk allergy in adults.

Symptoms

Milk allergy symptoms can be mild or severe. Many symptoms appear slowly over hours or days. However, some serious symptoms can occur quickly. A milk allergy in adults can have similar side effects.

Common milk allergy symptoms include:

• Diarrhea
• Blood in stool
• Stomach pain or cramps
• Runny nose
• Hives, or itchy bumps on your skin
• Watery eyes
• Excessive crying in infants

A serious symptom that requires immediate medical care is anaphylactic shock. This symptom usually occurs immediately after drinking milk and is potentially life threatening. A flushed face, a swollen throat, a sudden drop in blood pressure, and trouble breathing are signs of anaphylactic shock. Since this is a medical emergency, we strongly recommend anyone experiencing anaphylactic shock to seek medical care immediately.

Diagnosis

To diagnosis a milk allergy, your doctor will begin with a routine physical exam. He or she will likely inquire about your symptoms and medical history. Finally, your doctor will most often recommend additional tests to confirm the milk allergy diagnosis.

Additional milk allergy tests can include:

• Skin prick test – An allergy specialist will prick your skin and expose the area to a small sample of milk protein. If a rash, raised bumps or welts appear, then you may have a milk allergy.
• Blood test – Doctors will measure how your immune system reacts to milk. In particular, they will look at the amount of immunoglobulin E (IgE) antibodies in your blood, which can indicate possible milk allergies.
• Food challenge – An allergy specialist gives you or your child a small sample of a milk product to eat or drink. The specialist will then look for signs of an allergic reaction.
• Food tracking and elimination – Your doctor may ask you to track the food you eat every day, eliminate dairy products such as cow’s milk, and describe any changes in your symptoms. Food tracking can give your doctor vital information for identifying and diagnosing an allergic reaction to milk.

Causes

Milk allergies occur when your immune system malfunctions. Your immune system mistakenly interprets specific milk proteins as harmful. In defense, your immune system sends antibodies to counteract the proteins.  

Therefore, an allergic reaction to milk is really your body’s natural self-defense mechanism kicking in to protect itself. Your immune system releases chemicals like histamine that cause the symptoms of an allergic reaction. When identifying milk allergy causes, your doctor will look for Casein and Whey, the two proteins in cow’s milk responsible for causing most allergic reactions.

Risk Factors

There are several main risk factors for developing a milk protein allergy.

The risk factors for experiencing a milk allergy include:

• Age – Milk allergies occur more often in children than in adults. As children age, their digestive system develops more sophisticated and accurate responses to food.
• Family history – A child is more at risk for a milk allergy if one or both of their parents have any form of allergies.
• Other allergies – Most children with a milk allergy also have other allergies.
• Atopic dermatitis – Atopic dermatitis is also known as eczema, a common skin condition. Children with atopic dermatitis are more likely to develop a milk allergy.

Treatment

The best way to treat a milk allergy is to avoid milk and dairy products. Reading food and drink labels can often help to prevent allergic reactions. When reading labels, look for casein and whey, the two main types of milk proteins.

You can also manage the symptoms of an allergic reaction with antihistamines and epinephrine shots. Taking antihistamines can reduce and help manage the symptoms of a milk allergy. Antihistamines block the histamines in your body that cause the symptoms of allergic reactions. Your doctor may also want you and/or your child to carry an epinephrine injector in case of an emergency. An epinephrine shot helps manage anaphylactic shock. If you or your child experiences anaphylactic shock, please visit the emergency room as soon as possible.

What to Avoid with a Milk Allergy

What to avoid with a milk allergy? If you have a milk allergy, there are certain foods you can avoid to reduce or prevent allergic reactions. Checking labels, asking your doctor or pharmacist about the ingredients in medications, and discussing your allergy with waiters and chefs at restaurants can help prevent allergic reactions.

Common foods, drinks, and ingredients to avoid if you have a milk allergy:

• Whey
• Whey protein hydrolysate
• Casein
• Caseinates
• Casein hydrolysate
• Milk protein hydrolysate
• Diacetyl
• Ghee
• Lactose
• Lactulose
• Lactoferrin
• Lactalbumin
• Lactalbumin phosphate
• Rennet casein
• Tagatose
• Recaldent (R)
• Milk
• Powdered milk
• Condensed milk
• Derivative milk
• Dry milk
• Evaporated milk
• Animal milk
• Low-fat milk
• Malted milk
• Milkfat
• Fat-free milk
• Protein milk
• Skim milk
• Whole milk
• Milk solids
• Half-and-half
• Yogurt
• Custard
• Pudding
• Cream
• Cheese
• Cottage cheese
• Sour cream
• Sour cream solids
• Sour milk solids
• Butter
• Butter fat
• Butter oil
• Butter acid
• Butter esters
• Curds

If you and/or your child experience any of the signs and symptoms of a milk allergy, please reach out to an allergy specialist at Baptist Health today.