L-arginine (el-AHR-jih-nene) is a substance that's found in nuts, fish, red meat, soy, whole grains, beans and dairy products. It's also available in supplements.
Some people take L-arginine because it's believed to relax and open arteries, which might help lower blood pressure.
Research on L-arginine has had mixed results. But, the most recent research suggests that L-arginine may lower blood pressure. Still, larger and longer term studies need to be done to confirm that L-arginine supplements can reduce blood pressure before experts can recommend everyday use of these supplements.
Your body usually makes all the L-arginine it needs. Taking a supplement is rarely necessary and may be of benefit only to people who have a deficiency.
L-arginine supplements can interact with some medications, including nitroglycerin, some high blood pressure medications and erectile dysfunction medications. Don't take L-arginine supplements if you've had cold sores or genital herpes. Too much L-arginine in your system can trigger the virus that causes those conditions.
If you want to reduce your blood pressure, talk to your doctor about treatment options, including healthy lifestyle changes. If you have high blood pressure, talk to your doctor before starting any new herbal or dietary supplements, as these might adversely affect your blood pressure.