First Generation Antipsychotics

First-generation antipsychotics are used primarily for the treatment of psychosis.  Some first-generation antipsychotics have indications for treatment of nausea and vomiting.  Extrapyramidal side effects are common and include akathisia (restlessness), dystonia (prolonged muscle contraction), Parkinsonism (bradykinesia, rigidity, and tremors).  Side-effects are treated with benztropine or diphenhydramine.  Tardive dyskinesia refers to long-term side-effects caused by antipsychotics. Tardive dyskinesia includes repetitive movements such as lip-smacking and distinct. neck and trunk movements. 

Class Drugs

• Chlorpromazine

• Thioridazine

• Fluphenazine

• Haloperidol

• Loxapine

• Pimozide

• Thiothixene

• Trifluoperazine

Class Mechanism of Action

• Competitive blockade of D2 receptors

Class Application

Antipsychotic Effects

• Improves 'positive' symptoms of schizophrenia such as hallucinations, delusions, and paranoia

• Blocks D2 receptor in mesolimbic system

Antiemetic effects

• Blocks D2 receptors in medulla

Anticholinergic effects

• May help reduce extrapyramidal side effects

Class Adverse Effects

Extrapyramidal side effects

• Akathisia (restlessness)

• Dystonia (prolonged contraction of muscles)

• Parkinsonism (bradykinesia, rigidity, tremor)

• Treatments

Diphenhydramine and Benztropine

Tardive dyskinesia (abnormal repetitive movements: lip smacking and neck and limb movements)

• Long-term effect (occurs after both short-term and long-term use)

Anticholinergic effects

Neuroleptic malignant syndrome

• Muscle rigidity, fever, altered mental status, unstable blood pressure

• Therapy

Discontinue causative agent

• Supportive care

• May use dantrolene or bromocriptine

Weight Gain

• Often an issue resulting in patient non-compliance

Prolonged QT interval

Drug Table

Drug Name	Application	Comments	Image
Chlorpromazine			"Clorox" "Pro" "Magazine"
Thioridazine			"Theo" "Riding"
Fluphenazine			"Flu Shot" "Fence"
Haloperidol			"Halo" "Pear"
Loxapine			"Lock" "Pine Tree"
Pimozide			"Pimple" "Oz"
Thiothixene			"Theo" "Trix cereal"
Trifluoperazine			"Tricycle" "Flu Shot" "Pear"