An orexigenic, or<unk> , is a drug, hormone, or compound that increases<unk>  and may induce hyperphagia. This can be a medication or a naturally occurring neuropeptide hormone, such as ghrelin, orexin or neuropeptide Y, which increases hunger and therefore enhances food consumption. Usually<unk>  enhancement is considered an undesirable side effect of certain drugs as it leads to unwanted weight gain, but sometimes it can be beneficial and a drug may be prescribed solely for this purpose, especially when the patient is suffering from severe<unk>  loss or muscle wasting due to cystic fibrosis, anorexia, old age, cancer or AIDS. There are several widely used drugs which can cause a boost in<unk> , including tricyclic antidepressants (TCAs), tetracyclic antidepressants, natural or synthetic cannabinoids, first-generation antihistamines, most antipsychotics and many steroid hormones. In the United States, no hormone or drug has currently been approved by the FDA specifically as an orexigenic, with the exception of Dronabinol, which received approval for HIV/AIDS-induced anorexia only.
Appetite stimulant
Mood stabilizer
Antipsychotic
Antidepressant
Psychoactive drug
Atypical antidepressant
Antimanic drugs
Tricyclic antidepressant