Idebenone (pronounced eye-deb-eh-known) is an organic compound of the quinone family and promoted commercially as a synthetic analog of Coenzyme Q₁₀ (CoQ₁₀).

Idebenone is claimed to have properties similar to CoQ₁₀ in its antioxidant properties.^[specify]

Idebenone is different from Coenzyme Q₁₀ in one very important way. During a hypoxic (low oxygen) condition, CoQ₁₀ can switch function from an anti-oxidizing to an auto-oxidizing process. This auto-oxidation rapidly produces free radicals which damage the tissues of the body.^{[verification needed]}

Idebenone is said to perform the same functions as CoQ₁₀ without the risk of an auto-oxidation reaction.^{[verification needed]}

Idebenone is said to promote NGF (nerve growth factor) in the brain.^{[verification needed]} It appears to reduce tinnitus (ringing in the ears).^{[verification needed]} Idebenone has also been used in topical applications to treat wrinkles.

Takeda Pharmaceuticals studied Idebenone which it got approved for Alzheimer's disease and Stroke.