Antidepressant and Cholesterol-lowering Medication May Raise Blood Sugar

The lipid-lowering agent pravastatin (eg Pravachol, Apo-Pravastatin) and the antidepressant paroxetine (eg Paxil, Seroxat CR, Apo-Paroxetine) are among the most widely prescribed drugs in the world. Unexpected interactions between them could have important public health implications.

If you are currently taking both pravastatin and paroxetine, you should be interested to know that a new study finds these two drugs taken in combination appear to significantly raise blood sugar levels.

The increase is most apparent -- and concerning -- among diabetics, whose blood sugar is already too high, the researchers noted.

Neither drug alone raises blood sugar, and the researchers said they can't yet explain the effect of the combination. Combinations of other antidepressants and cholesterol-lowering drugs do not boost glucose levels, it is not a ‘class effect’.

The researchers mined the US Food and Drug Administration's (FDA's) Adverse Event Reporting System (AERS) for side-effect profiles involving glucose homeostasis and found a surprisingly strong signal for comedication with pravastatin and paroxetine. They identified 135 non-diabetic patients taking both drugs whose blood sugar increased 19 milligrams per deciliter (1.0 millimole per liter) after starting treatment. They also identified 104 diabetics whose blood sugar increased an average of 48 mg/dl (2. 7 mmol/l) while taking both drugs.

If you are currently taking both pravastatin and paroxetine, it would be reasonable to visit your doctor soon and see if your glucose levels have been difficult to control.

"If it has been, then I would think the thing to change might be the statin," said Dr. Ronald B. Goldberg., professor of medicine at the Diabetes Research Institute of the University of Miami Miller School of Medicine,

"People with diabetes have an increased risk of depression; they are all recommended to be on statins," Goldberg said. "So, it may aggravate blood sugar control in people who are diabetic."

Goldberg thinks it's too early to change clinical practice based on this study alone. "This needs to be confirmed in a clinical trial," he said.

Source:

1. N P Tatonetti, J C Denny, S N Murphy, G H Fernald, G Krishnan, V Castro, P Yue, P S Tsau, I Kohane, D M Roden, R B Altman. Detecting Drug Interactions From Adverse-Event Reports: Interaction Between Paroxetine and Pravastatin Increases Blood Glucose Levels. Clin Pharmacol Ther advance online publication, May 25, 2011; doi:10.1038/clpt.2011.83

2. MSN Health

3. People with blood sugar levels of 126 mg/dl (7.0 mmol/l) or higher on two tests are considered diabetic. Levels of 100 mg/dl to 125 mg/dl (5.5 mmol/l to 6.94 mmol/l) are considered pre-diabetic