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Lactose allergy
Last reviewed: 05.07.2025

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Lactose allergy (or, in medical terms, lactose intolerance, lactase deficiency) is an unpleasant phenomenon that, contrary to popular belief, plagues adults no less than newborns and preschool children.
It is important to clearly understand the difference between milk allergy and lactose intolerance. Lactose is a complex sugar found in milk and all dairy products and is digested with the help of the enzyme lactase. If a person suffers from a low level of lactase, then he/she cannot avoid an allergy (intolerance) to lactose. However, people with increased sensitivity to lactose, unlike those who suffer from milk allergy, may not exclude calcium-rich dairy products from their diet.
Causes of lactose allergy
Very often people say that they don’t like milk, not realizing that they actually suffer from lactose intolerance.
The reasons for which lactose intolerance (or lactose allergy) occurs can be associated with both congenital dysfunction of the body and as a result of acquired diseases.
The most common causes of lactose allergy are:
- Congenital lactase deficiency (an enzyme that breaks down lactose in dairy products). It should be noted that this disease is very rare and is most common in countries where cow's milk is not consumed (South America, Africa, Asia).
- Individual characteristics of the human body. Starting from the age of two, a natural process occurs in the human body - a decrease in lactase levels. Depending on individual characteristics, this process may go unnoticed. If the decrease is too significant, then lactose intolerance for an adult is almost inevitable.
Secondary lactase deficiency. The causes are:
- Diseases that affect the small intestine (inflammatory processes, flu, etc.). In this case, lactose allergy disappears after the disease is completely cured.
- Surgical intervention – operations on the stomach or intestines, which permanently deprive the body of the ability to produce the enzyme lactase.
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Symptoms of lactose allergy
Often, the symptoms of lactose intolerance resemble food poisoning. In this case, you should pay attention to the products that a person has eaten recently.
Symptoms of lactose allergy occur within approximately 30 minutes after consuming any dairy product (cottage cheese, homemade cheese, ice cream):
- Abdominal pain of a cramping nature (spasms).
- Bloating, which causes increased gas formation in the intestines.
- Diarrhea, loose stools.
- In rare cases – fever and vomiting.
Lactose allergy in children
Almost all children from the age of two years experience lactose allergy (lactase deficiency). This phenomenon is considered absolutely normal, since with age a person's need for milk decreases and up to six years a natural decrease in lactase production occurs in the child's intestines. But, despite the apparent safety of the genetic process, for newborns and infants, lactose allergy can become a fatal disease due to severe accompanying symptoms that can provoke complete exhaustion of the child's body (incessant vomiting, diarrhea, inability to digest the main food - milk).
Lactose allergy in newborns
For newborns and infants, lactose allergy is especially dangerous, because their main diet consists of mother's milk, which is rich not only in all the necessary vitamins, but also in a large amount of lactose.
Most often, premature or immature babies suffer from lactose intolerance.
Symptoms of lactose allergy in children:
- The child is restless while taking milk (the child starts eating with appetite, but after a few minutes begins to cry, refuses the breast, and pulls his legs up to his stomach).
- Bloating and increased gas production.
- Liquid foamy stool.
- Red rashes on the skin.
Lactose allergy can occur both during breastfeeding and when feeding a child with artificial mixtures (if cow's milk protein or soy is added to them).
In order to relieve the child from a dangerous ailment, it is necessary to undergo a medical examination and transfer the baby to a lactose-free diet - usually such measures are enough to completely get rid of lactase deficiency.
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Diagnosis of lactose allergy
In both adults and children, diagnosis of lactose allergy is a series of completely painless procedures.
It is often not difficult to identify lactase deficiency on your own; this can be done by tracking the connection between the onset of symptoms of the disease and the consumption of dairy products.
For a more detailed examination, several types of tests are usually used:
- Analysis of feces for carbohydrate content, blood for glucose content after drinking milk.
- Analysis test for hydrogen levels (the amount of hydrogen exhaled is directly related to undigested lactose).
- In rare and particularly complex cases, an analysis of the small intestinal mucosa (biopsy) is performed.
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Treatment of lactose allergy
The most important point in the treatment of lactase deficiency is a special diet with a low content or complete exclusion (for newborns) of the cause of the allergy - lactose.
Adults are allowed to consume fermented milk products (kefir, cheeses, yogurt, etc.) in small quantities, as well as include calcium-containing foods (fish, almonds, etc.) in their diet.
In case of lactose allergy, surgical interventions and physiotherapy are not provided, as well as drug treatment. But to improve the general condition of the patient, the doctor can prescribe enzyme preparations:
- "Lactase" is taken by adults 3 tablets before consuming dairy products or 1 capsule per day if the patient is already taking similar medications or vitamins.
- "Lactase Baby" is prescribed to newborns and children up to 7 years old. Depending on the degree of intolerance, the contents of 1-7 capsules of the drug are added to children's food.
Folk remedies are ineffective in combating lactose allergy, although, in order to alleviate the general condition, you can take a decoction of herbs that have an anti-inflammatory effect:
- For diarrhea: yarrow, wormwood, horsetail, cinquefoil roots - two tablespoons of equal amounts of dry pharmaceutical herbs are poured with 0.5 boiling water and infused for 2 hours. Take warm, half a glass 3 times a day.
- For bloating and increased gas formation: pour a tablespoon of chamomile into a glass of hot water and boil for 5 minutes; leave to infuse for 4 hours and take two tablespoons before meals.
More information of the treatment
Prevention of lactose allergy
Unfortunately, it is impossible to avoid lactose allergy, which is caused at the genetic level. However, people who suffer from lactase deficiency should be pleased with the fact that they do not have to limit their consumption of dairy products completely (unlike those who suffer from milk allergy). In order to save yourself from unpleasant consequences, it is enough to follow some rules:
- Milk can be consumed in small quantities (no more than 200 ml) and only with food.
- Those who suffer from lactose intolerance can usually tolerate cheese (mozzarella, parmesan, cheddar) and yogurt in small quantities quite well.
- In order for the body not to suffer from a lack of calcium, it is necessary to eat “milk substitutes”: fish, soy milk, green vegetables, almonds, etc.
- Carefully study the composition of products and instructions for medications that may contain lactose; monitor the food served in cafes and restaurants.
It is worth remembering that no one is immune from the so-called acquired allergy to lactose. Therefore, in order to avoid such troubles, you need to pay close attention to the health of the digestive system (stomach, intestines), avoid problems with the gastrointestinal tract, and promptly and under the supervision of a specialist treat diseases of the stomach and intestines.
Lactose allergy (or lactase deficiency) is a phenomenon that cannot be called a disease, since it is temporary and can be dealt with fairly quickly and without much effort if you make a habit of paying close attention to your own health.