Liver Injury in a Person Taking the Diabetes Drug Rosiglitazone

What is the problem and what is known about it so far?

High levels of blood sugar in diabetic patients contribute over time to complications such as blindness and kidney failure. The goal of diabetes treatment is therefore to keep blood sugar levels normal, but treatment often involves daily injections of insulin. The thiazolidinediones are a new class of diabetes drugs in pill form that lower blood sugar levels. Unfortunately, the first approved drug in this class, troglitazone, can cause severe liver damage in a small percentage of people. It is not yet known whether the second drug in this class, rosiglitazone, is associated with severe liver problems.

Why did the researchers do this particular study?

They observed liver damage in a patient taking rosiglitazone.

Who was studied?

A 61-year-old man who had been taking rosiglitazone 4 mg per day.

How was the study done?

The authors reviewed the patient's medical records.

What did the researchers find?

After taking rosiglitazone for 8 days, the patient had developed nausea, vomiting, decreased appetite, and abdominal pain, but he continued taking the drug. One week later, he was hospitalized with worsening symptoms. In addition to diabetes, the patient had lung disease and a history of alcoholism in the distant past. Eight months before this hospital admission, the patient had started taking a related diabetes drug, troglitazone, but stopped it because of abdominal pain. His liver function had been normal at that time. He had also taken repaglinide, a diabetes medication from a different class of drugs, starting 7 weeks before hospitalization but stopped it after 5 weeks because of nausea and dizziness. He then started rosiglitazone. The patient's other medications were acetaminophen (Tylenol) and drugs for his lung disease.

Liver tests were markedly abnormal in the hospital. The patient's doctors discontinued the rosiglitazone and gave the patient supportive care. Extensive tests showed no other cause for the liver damage. Blood levels of acetaminophen, which can cause liver damage, were very low. By the second day of hospitalization, the patient's symptoms resolved. His liver tests initially worsened, then slowly became normal over the next month.

What were the limitations of the study?

It is impossible to know for sure in this single patient whether rosiglitazone caused the liver failure. The patient was also taking acetaminophen, which can cause liver damage at high doses, but blood levels of this drug were low; alcohol can also cause liver damage, but the patient denied drinking alcohol recently. The drugs that the patient was taking for his lung disease could have contributed to the damage, but they have not been associated previously with liver toxicity.

What are the implications of the study?

Liver damage may possibly occur in patients who take rosiglitazone. Patients taking this drug should have their liver tests watched carefully, and should discontinue the drug if symptoms develop.