CHE 360 - antipsychotics

Schizophrenia

due to an overproduction of dopamine or oversensitivity of dopamine receptors in the mesolimbic and mesocortical areas of the brain

positive symptoms

eligious, grandiose, or persecutory delusions, hallucinations (auditory and/or visual) paranoia, thought disorders, withdrawal – violence to objects, other people and themselves may occur

negative symptoms

apathy lack of motivation inability to think and communicate clearly lack of energy withdrawal from society

dopamine

neurotransmitter in the brain

Extrapyramidal reactions

drug-induced movement disorders caused by medications that block dopamine receptors in the brain, most commonly first-generation antipsychotics and antiemetics

Tardive dyskinesia

writhing movements of tongue and face, “fly-catching” motion, lip smacking – progresses into involuntary movement of limbs and trunk. Geriatrics are at particular risk.

haloperidol (Haldol)

Used for treatment of schizophrenia. Short term use to sedate severe behavior problems. IM depot injections are ones that create a long-term (2-4 weeks) supply of the drug in fat tissue that is slowly released over time

olanzapine (Zyprexa)

Weight gain is a particularly common problem, as well as hyperglycemia. 16% of olanzapine patients gained at least 30 kg (66 pounds). By 2009, manufacturer Eli Lilly had paid $1.2 billion to settle 8,000 lawsuits from people who said they had developed diabetes or other diseases after taking ———-. Thousands more suits are still pending. Lilly also paid 1.42 billion dollars for illegal marketing of off label uses of Zyprexa, particularly to treat Alzheimer’s dementia.

quetiapine(Seroquel)

(generic available, patent expired 2012)

weight gain and sedation are common problems

Aripiprazole(Abilify)

(generic available, patent expired 2015)

less weight gain than other atypicals

Specific atypical drugs

olanzapine (Zyprexa), quetiapine(Seroquel), aripiprazole (Abilify)

Antiemetic

reduce nausea and vomiting. Surgery, severe flu, and chemotherapy can all cause serious nausea and vomiting, and these effects can be reduced or eliminated with the use of. Clinicians noticed that several of the antipsychotic drugs showed antiemetic activity, andsynthesis of a large number of molecules similar to chlorpromazine or haldol produced several drugs effective at reducing nausea.

CTZ (chemical trigger zone)

sometimes described as a circumventricular organ, due to its extensive vasculature and lack of BBB, but it is contiguous with the rest of the medulla oblongata. Blocking of dopamine receptors in the ______ produces inhibition of nausea and vomiting.

prochlorperazine (Compazine)

is effective for most forms of nausea (e.g. post-surgical nausea), but has been less effective for treating nausea associated with cancer chemotherapy.

ondansetron (Zofran)

work to reduce nausea by blocking serotonin receptors in CTZ and vagal nerve terminals, reducing vagal nerve stimulation of the CTZ. They are very effective in reducing the nausea immediately after cancer chemotherapy, should be taken both before and after chemotherapy.

marijuana

Proponents of legalized ______ use have claimed that THC provides relief of anorexia associated with AIDS and nausea related to chemotherapy.

dronabinol (Marinol)

a synthetic form of one of the active ingredients of marijuana, helps with nausea