An aphrodisiac or love drug is a substance that increases sex drive when consumed. Aphrodisiacs are distinct from substances that address fertility issues or secondary sexual (dys)function such as erectile dysfunction.

The name comes from the Greek ἀφροδισιακόν, aphrodisiakon, i.e. "sexual, aphrodisiac", from aphrodisios, i.e. "pertaining to Aphrodite",[1][2] the Greek goddess of love. The opposite substance is an anaphrodisiac.

Throughout human history, food, drinks, and behaviors have had a reputation for making sex more attainable and/or pleasurable. However, from a historical and scientific standpoint, the alleged results may have been mainly due to mere belief by their users that they would be effective (placebo effect). Likewise, many medicines are reported to affect libido in inconsistent or idiopathic ways:[3] enhancing or diminishing overall sexual desire depending on the situation of the subject. For example, Bupropion (Wellbutrin) is known as an antidepressant that can counteract other co-prescribed antidepressants having libido-diminishing effects. However, because Wellbutrin only increases the libido in the special case that it is already impaired by related medications, it is not generally classed as an aphrodisiac.

Yohimbine, Spanish fly, mad honey, and bufo toad have no scientific evidence of providing aphrodisiac effects.[3] While numerous plants, extracts or manufactured hormones have been proposed as aphrodisiacs, there is little high-quality clinical evidence for the efficacy or long-term safety of using them.[3][4]

Libido in males is linked to levels of sex hormones, particularly testosterone.[4][5][6] When a reduced sex drive occurs in individuals with relatively low levels of testosterone, particularly in postmenopausal women or men over age 60,[7] testosterone dietary supplements have been used with intent to increase libido, although with limited benefit.[4][7] Long-term therapy with oral testosterone is associated with increased risk of cardiovascular diseases.[8]

Amphetamine and methamphetamine are phenethylamine derivatives which are known to increase libido and cause frequent or prolonged erections as potential side effects, particularly at high supratherapeutic doses where sexual hyperexcitability and hypersexuality can occur;[9][10][11][12] however, in some individuals who use these drugs, libido is reduced.[10][12]

The invention of an aphrodisiac is the basis of a number of films including Perfume: The Story of a Murderer, Spanish Fly, She'll Follow You Anywhere, Love Potion No. 9 and A Serbian Film. The first segment of Woody Allen's is called "Do Aphrodisiacs Work?", and casts Allen as a court jester trying to seduce the queen.