Allergic Reactions to Soy Milk

Fact Checked

iView Stock/View Stock/Getty Images

If you’re allergic to soy, you will experience an allergic reaction if you drink soy milk, which is commonly used to substitute for dairy. It is made from soy beans, water, sugar and flavoring. If you’ve been clinically diagnosed with a soy allergy, avoid drinking soy milk. Soy milk can cause gastrointestinal, skin and respiratory reactions. Any reaction you experience should be disclosed to your doctor.


All allergic reactions to soy milk are a result of a malfunction of the immune system. Although soy proteins are safe for human consumption, if you’re allergic to soy, your immune system identifies the proteins as unsafe. The body creates antibodies and histamine to fight off the allergen, according to MedlinePlus. Histamine is a chemical in the body that helps protect it from infection, but in large quantities, it can cause inflammation. The inflammation from histamine is what causes most allergic reactions.

Gastrointestinal Reactions

One of the first places you may develop symptoms after drinking soy milk is in your gut. Inflammation and irritation in the digestive tract can cause nausea, vomiting, diarrhea, stomach pain and cramping, according to the Cleveland Clinic. Most symptoms will develop within a few minutes after you drink soy milk and should only last for a few hours. If your gastric symptoms are longer than a few hours, call your doctor. Excessive diarrhea and vomiting can lead to dehydration, which can cause complications, such as brain damage and death.

Skin Reactions

Your skin may develop a rash after you drink soy milk. Allergic skin reactions can appear anywhere on your body, but mostly develop on your face, around your mouth or on your limbs. Common skin reactions include hives and eczema, according to Hives are clusters of welts that are flat on top and have defined borders that appear in various shapes and sizes. Eczema forms as small blisters that can crack weep and crust over. In severe cases, eczema can cause permanent scarring.

Respiratory Reactions

Respiratory reactions may include nasal congestion and asthma symptoms. Nasal irritation can cause a runny nose, sneezing and sinus pressure. As the sinus cavity becomes inflamed, the nasal passages swell, placing excessive pressure on the surrounding areas of the head. Asthma symptoms include shortness of breath, chest tightness, wheezing, coughing, the inability to breathe and chest pain.