Medicine to Trigger a Gallbladder Attack

Nearly 1 million Americans undergo gallbladder surgery each year. While doctors have known for years that age, obesity, diabetes and multiple pregnancies can raise the risk of gallbladder disease, scientists have learned that certain drugs may trigger a gallbladder attack. Cholesterol-lowering medicine, and estrogen and progestin, female hormones used to counteract the symptoms of menopause, create more risks.

Risk factors

• Too much cholesterol can lead to gallstones in your gallbladder, occasionally triggering a painful attack. Your gallstone chances increase with age, obesity, multiple pregnancies and diabetes. Research shows that hormone replacement therapy, birth control pills and cholesterol-lowering drugs also pose substantial risks.

Hormone therapy

• In 2005, researchers learned that postmenopausal women taking estrogen have a higher risk of gallbladder disease and surgery. Taking progestin, another hormone therapy, did not affect their risk.

  The study, part of the Women's Health Initiative that revealed the dangers of hormone replacement therapy, followed 22,000 women for up to seven years. Researchers divided women into two groups, those who had had hysterectomies and those who hadn't. Those with hysterectomies took either estrogen or a placebo. Women who had not had the surgery received estrogen and progestin or a placebo.

  The women who took estrogen alone had a 67 percent higher risk of getting gallbladder disease or requiring surgery. Those taking both hormones increased their risk by 59 percent. Women taking estrogen alone were also 80 percent more likely to experience gallbladder inflammation. When a gallstone blocks the flow of bile, inflammation may result. Patients who took the estrogen-progestin combination had a 54 percent rise in inflammation risk. The estrogen patients also experienced an 86 percent higher risk of forming gallstones, while women taking the combination therapy had a 68 percent higher risk.

  Estrogen probably changes the nature of bile, making it more saturated and forming stones that block the gallbladder and its duct, sometimes triggering inflammation, said study co-author Dr. Robert B. Wallace, an epidemiology professor at the University of Iowa College of Public Health.

Cholesterol-lowering drugs

• While women are three times as likely as men to develop gallbladder disease, men may escalate their risks by taking cholesterol-reducing drugs. Some of these drugs, especially fibrates, can stimulate gallstone formation because they add more cholesterol to the bile. Medicines that boost the risk include gemfibrozil, or Lopid; fenofibrate, or Tricor; and bezafibrate, or Bezalip. If you're concerned about the risks, talk to your doctor before starting on any of these drugs. She can help you weigh the medicine's risks, compared to other solutions for menopause symptoms or high cholesterol levels.