Antiplatelet and anticoagulant drugs (blood-thinners) -- Rosemary may affect the blood's ability to clot, and could interfere with any blood-thinning drugs you are taking, including:

• Warfarin (Coumadin)
• Clopidogrel (Plavix)
• Aspirin

ACE inhibitors -- Rosemary may interfere with the action of ACE inhibitors taken for high blood pressure.

• Captpril (Capoten)
• Elaropril (Vasotec)
• Lisinopril (Zestril)
• Fosinopril (Monopril)

Diuretics (water pills) -- Because rosemary can act as a diuretic, it can increase the effects of these drugs, raising the risk of dehydration:

• Furosemide (Lasix)
• Hydrocholorothiazide

Lithium -- Because of its diuretic effects, rosemary might cause the body to lose too much water and the amount of lithium in the body to build up to toxic levels.

Diabetes -- Rosemary may alter blood sugar levels and could interfere with any drugs taken to control diabetes.