Fluphenazine

A 2018 Cochrane review found that fluphenazine was an imperfect treatment and other inexpensive drugs less associated with side effects may be an equally effective choice for people with schizophrenia. Another 2018 Cochrane review found that there was limited evidence that newer atypical antipsychotics were more tolerable than fluphenazine. Intramuscular depot injection forms are available as both the decanoate and enanthate esters. ==Side effects==

Discontinuation The British National Formulary recommends a gradual withdrawal when discontinuing antipsychotics to avoid acute withdrawal syndrome or rapid relapse. Symptoms of withdrawal commonly include nausea, vomiting, and loss of appetite. Other symptoms may include restlessness, increased sweating, and trouble sleeping. It may also result in reoccurrence of the condition that is being treated. Rarely tardive dyskinesia can occur when the medication is stopped. ==Pharmacology==

Pharmacodynamics Fluphenazine acts primarily by blocking post-synaptic dopaminergic D2 and D1 receptors in the basal ganglia, cortical and limbic system. Fluphenazine depresses both the release of hypothalamic and hypophyseal hormones and the reticular activating system. The volume of distribution is about 298 L due to extensive tissue uptake, and it crosses the blood brain barrier. and the half-life is about 14–16 hours. Due to the lipophilicity of the added decanoate or enanthate group, the drug remains in the oil causing the rate-limiting step for drug being diffusion out, resulting in flip-flop kinetics. The fluphenazine decanoate acts within 1–3 days, and its effect lasts an average of 2 weeks. and plasma levels peak at about 2.18 ng/mL about 4–6 hours post injection. Fluphenazine enanthate has a lower half life of about 3.6-3.7 days, reflecting its decreased lipophilicity. ==Availability==

The injectable form is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. It was discontinued in Australia in 2017. == Veterinary ==

In horses, it is sometimes given by injection as an anxiety-relieving medication, though there are many negative common side effects and it is forbidden by many equestrian competition organizations. == References ==