NADH stands for "nicotinamide adenine dinucleotide (NAD) + hydrogen (H)." This chemical occurs naturally in the body and plays a role in the chemical process that generates energy. People use NADH supplements as medicine.

NADH is used for improving mental clarity, alertness, concentration, and memory; as well as for treating Alzheimer’s disease and dementia. Because of its role in energy production, NADH is also used for improving athletic performance and treating chronic fatigue syndrome (CFS).

Some people use NADH for treating high blood pressure, high cholesterol, jet lag, depression, and Parkinson’s disease; opposing alcohol’s effects on the liver; reducing signs of aging; and protecting against the side effects of an AIDS drug called zidovudine (AZT).

Healthcare providers sometimes give NADH by intramuscular (IM) or intravenous (IV) injection for Parkinson's disease and depression.

NADH produced by our bodies is involved in making energy in the body. While there is some evidence that suggests NADH supplements might reduce blood pressure, lower cholesterol, help chronic fatigue syndrome by providing energy, and increase nerve signals for people with Parkinson's disease, there isn't enough information to know for sure how or if these supplements work.