Apomorphine, sold under the brand name Apokyn among others, is a type of aporphine having activity as a non-selective dopamine agonist which activates both D2-like and, to a much lesser extent, D1-like receptors. It also acts as an antagonist of 5-HT2 and α-adrenergic receptors with high affinity. The compound is historically a morphine decomposition product made by boiling morphine with concentrated acid, hence the -morphine suffix. Contrary to its name, apomorphine does not actually contain morphine or its skeleton, nor does it bind to opioid receptors. The apo- prefix relates to it being a morphine derivative ("[comes] from morphine"). Historically, apomorphine has been tried for a variety of uses, including as a way to relieve anxiety and craving in alcoholics, an emetic (to induce vomiting), for treating stereotypies (repeated behaviour) in farmyard animals, and more recently in treating erectile dysfunction. Currently, apomorphine is used in the treatment of Parkinsons disease. It is a potent emetic and should not be administered without an antiemetic such as domperidone. The emetic properties of apomorphine are exploited in veterinary medicine to induce therapeutic emesis in canines that have recently ingested toxic or foreign substances. Apomorphine was also used as a private treatment of heroin addiction, a purpose for which it was championed by the author William S. Burroughs. Burroughs and others claimed that it was a "metabolic regulator" with a restorative dimension to a damaged or dysfunctional dopaminergic system.
The 1965 Tuli Kupferberg song "Hallucination Horrors" recommends apomorphine at the end of each verse as a cure for hallucinations brought on by a humorous variety of intoxicants; the song was recorded by The Fugs and appears on the album Virgin Fugs. Research
There is renewed interest in the use of apomorphine to treat addiction, in both smoking cessation and alcoholism. As the drug is known to be reasonably safe for use in humans, it is a viable target for repurposing. Apomorphine has been researched as a possible treatment for erectile dysfunction and female hypoactive sexual desire disorder, though its efficacy has been limited. Nonetheless, it  was under development as a treatment for erectile dysfunction by TAP Pharmaceuticals under the brand name Uprima. In 2000, TAP withdrew its new drug application after an FDA review panel raised questions about the drugs safety, due to many clinical trial subjects fainting after taking the drug. Alzheimers disease
Apomorphine is reported to be an inhibitor of amyloid beta protein fiber formation, whose presence is a hallmark of Alzheimers disease, and a potential therapeutic under the amyloid hypothesis. Alternative administration routes
Two routes of administration are currently clinically utilized: subcutaneous (either as intermittent injections or continuous infusion) and sublingual. Other non-invasive administration routes were investigated as a substitute for parenteral administration, reaching different preclinical and clinical stages. These include: peroral, nasal, pulmonary, transdermal, rectal, and buccal, as well as iontophoresis methods. Veterinary use
Apomorphine is used to inducing vomiting in dogs after ingestion of various toxins or foreign bodies.