Q. I get pressure and pain in my upper abdomen after meals. An ultrasound showed no gallstones, and my doctor can't figure out what I have. I'm 38, have not lost weight, and had normal blood tests.

A. You sound like Ms. C, a 32-year-old patient described in the February 2008 Journal of the American Medical Association. She had upper abdominal aching lasting for hours three or four times a week, worse after fatty meals. She often felt full after only a little food, and also had heartburn. Antacid pills like omeprazole (Prilosec) relieved the heartburn behind her chest, but not the pain related to fatty meals.

After undergoing various tests, Ms. C was diagnosed as having both heartburn and something called functional dyspepsia, which is what I think you may have. Studies in such patients have shown delayed emptying of food from the stomach, increased stomach tone (in about 40 percent) and/or abnormal stomach or intestinal contractions. There's often oversensitivity to stretching of the stomach or intestinal wall. All the above can be worsened by psychosocial factors like anxiety.

The exact cause can't be determined in the individual patient. It's a common condition that does not lead to cancer or anything serious. Functional dyspepsia is upper abdominal discomfort (sometimes burning pain) or bothersome fullness occurring several times a week after eating even normal-sized meals. There may be belching, bloating or nausea.

We call it functional dyspepsia if it's been there for six months and we find no evidence of other disease. For instance, folks who take high doses of aspirin or regular doses of ibuprofen, naproxen or other anti-inflammatories for months may have ulcers. Diabetics may have delayed emptying of food, for which specific drugs may help.

If there's weight loss, trouble swallowing, recurrent vomiting, bloody or black stools, anemia, abdominal distension or unusual fatigue, then see a doctor immediately.

Antibiotics cure some dyspeptics who have H. pylori, a germ that can cause ulcers, so get tested for this. Get the stool antigen rather than blood test, as the latter is not as accurate under age 40. But folks in their 50s and older should instead get endoscopies, so doctors can also test for H. pylori.

If this doesn't work, try a daily omeprazole pill at least four to six weeks, then stop — your pain may not return. If it does, restart the pill but try stopping it every six to 12 months.

If omeprazole fails, try behavioral therapy or low-dose Elavil or Norpramin.

Don't despair — one-half to two-thirds of folks will improve or be pain-free within five years.