DEAR DR. DONOHUE: Ice cream is my passion. But I think my days of eating it are gone. I had a big bowl three weeks ago, and that night and the next day I was in agony. I had bad cramps and diarrhea. The following day everything returned to normal. I thought I might have had a touch of stomach flu. Last night I ate some more ice cream with the same reaction. Have I become allergic to it? — C.L.

ANSWER: It’s less likely to be an allergy and more likely to be an intolerance to lactose, milk sugar. All dairy products have some lactose. Our small intestine is equipped with an enzyme, lactase, that breaks down lactose into two smaller sugars that are easily digested. People who lack that enzyme are said to be lactose intolerant or lactase deficient. Both terms mean the same thing.

We are born with a good supply of the lactase enzyme. Infants are dependent on it, since most of their nutrition comes from milk. With age, the lactase enzyme supply dwindles. Adult Asians, Native Americans and blacks are the ethnic groups where lactase deficiency is most pronounced. The signs of lactase deficiency are painful abdominal cramps with diarrhea upon eating dairy foods.

A doctor can prove that you are deficient in the enzyme in a number of ways. A lactose-tolerance test is performed by giving a patient a dose of lactose and then measuring blood sugar at one and two hours. If a person has the lactase enzyme, blood sugar will rise because one of the sugars produced by the enzyme is glucose — blood sugar. If the person is lactase deficient, blood sugar won’t rise.

Treatment is avoidance of dairy products. Not all dairy products produce symptoms. Cheese usually is well tolerated. So is butter.

Another way to deal with lactase deficiency is to take the lactase enzyme by mouth before eating dairy foods. Or you can add the enzyme to dairy products. Manufacturers have pretreated many foods with lactase, including milk.

DEAR DR. DONOHUE: Since childhood I have suffered with bouts of nausea. Now, at age 70, I have been diagnosed with a large bezoar. Is it possible I had this since childhood?

I have been on cellulase for six months, with little noticeable improvement. My surgeon is reluctant to remove it because of my failing heart. Information on bezoars on the Internet is scarce. Will you please discuss it? — J.T.

ANSWER: Bezoars (BEE-zores) are rarely discussed these days. They’re balls of indigestible matter that form in the stomach. Hair is one material that forms a bezoar. Some vegetable components also can become one. As the bezoar grows, it blocks the passage of food out of the stomach. Symptoms include a sense of fullness after only a few mouthfuls of food, stomach pain, vomiting and weight loss. It’s unlikely that you have had this since childhood.

Your cellulase is an enzyme that can digest a bezoar. Apparently, it’s not working for you. Are you in good enough health to have a gastroscope passed into your stomach? It’s inserted through the mouth and doesn’t place a huge physical burden on the heart. A doctor can remove a bezoar with the help of such a scope.

DEAR DR. DONOHUE: Please answer this question. Where can I get a tiny bottle of smelling salts? — D.R.

ANSWER: Smelling salts is ammonium carbonate. The fumes of smelling salts irritate the nasal lining and serve as a stimulant for a person who has fainted.

Have you tried local drugstores? If your drugstore doesn’t carry smelling salts, ask the pharmacist to order some for you. I have seen smelling salts advertised on the Internet. I haven’t seen it in small bottles. It’s most often sold in boxes that contain individual containers that are broken to release the fumes.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from