LACTOSE INTOLERANCE

General Information

DEFINITION--Difficulty digesting cow's milk. Lactose is the primary sugar in milk. Lactose intolerance occurs--with varying severity--in 75% of the black population, 90% of Orientals or American Indians, and less than 20% of Caucasians of northwest European origin. It is not contagious or cancerous.

BODY PARTS INVOLVED--Digestive system.

SEX OR AGE MOST AFFECTED--Both sexes; all ages.

SIGNS & SYMPTOMS

In children:

• Foamy diarrhea with diaper rash.
• Vomiting (sometimes).
• Slow weight gain, growth and development.

In adults:

• Rumbling abdominal sounds, abdominal cramps and diarrhea.
• Gas and bloating.
• Nausea.

CAUSES--Deficiency or absence of the enzyme lactase. Lactase is necessary to digest all milk except mother's milk. Without it, sugars in milk absorb fluid and cause diarrhea. Although some infants are born with the disorder, lactose intolerance usually develops in adulthood. Temporary lactose intolerance can occur in an infant after a severe bout of gastroenteritis that damages the intestinal lining.

RISK INCREASES WITH--Family history of enzyme-lactase deficiency.

HOW TO PREVENT--Cannot be prevented at present. If you are pregnant and there is a history of lactose intolerance in your family, consider breast-feeding your baby. If not, you may need an alternate non-milk formula.

What To Expect

DIAGNOSTIC MEASURES--

• Your own observation of symptoms.
• Medical history and physical exam by a doctor.
• Laboratory studies, such as a stool exam and lactose-tolerance test.

APPROPRIATE HEALTH CARE

• Self-care after diagnosis.
• Doctor's treatment.

POSSIBLE COMPLICATIONS--Calcium deficiency (rare).

PROBABLE OUTCOME--This condition is currently considered incurable. However, symptoms can be relieved or controlled with a diet free of milk and milk products. Symptoms worsen at times for unexplained reasons.

How To Treat

GENERAL MEASURES----Symptoms can be controlled by diet restrictions or use of lactase products.

MEDICATION--

• A supplement to neutralize lactose in milk. The enzyme lactase is available without a prescription to be added to milk and milk products and products are available that have the enzyme added already.
• Calcium supplements may be recommended.

ACTIVITY--No restrictions.

DIET--

• If the condition is present at birth, an infant formula that contains little or no lactose, such as a soybean-based formula, will be recommended.
• If the lactose intolerance is temporary and caused by gastroenteritis, the substitute formula should be necessary for a short time only. Cow's milk can be introduced again later.
• Older persons with lactose intolerance should reduce or restrict milk and milk products, such as cheese and ice cream. Some patients tolerate whole milk or chocolate milk better than skim.
• Yogurt and fermented products such as hard cheese are better tolerated than milk.
• Read labels on food products. Milk-sugar is used in many and may cause symptoms.

Call Your Doctor If

• You or your child have symptoms of lactose intolerance.
• Temperature rises to 101F (38.3C) or higher.
• Your infant fails to gain weight.
• Your infant refuses food or formula.
• Vomiting or diarrhea reappears in a child who has previously had a temporary intolerance to milk or milk products.
• A milk-free diet doesn't relieve symptoms.