Delusions of Parasitosis Medication
- Author: Noah S Scheinfeld, MD, JD, FAAD; Chief Editor: Dirk M Elston, MD more...
Medication Summary
The current treatment of choice is risperidone[34, 35] or olanzapine.[36, 37, 38] The older treatment of choice is pimozide.[39] Several more recent articles have suggested other psychiatric medications can be used to treat delusions of parasitosis, including escitalopram (Lexapro, Forest Pharmaceuticals; New York, NY)[40] and aripiprazole.[41]
The most common adverse effects of pimozide are extrapyramidal symptoms, including stiffness and, occasionally, a special inner sense of restlessness called akathisia. Effective treatment of such extrapyramidal reactions includes benztropine 1-2 mg up to 4 times daily as needed or diphenhydramine 25 mg 3 times daily.
Antipsychotics
Class Summary
Used to treat psychoses.
Risperidone (Risperdal)
Binds to dopamine D2 receptor with 20 times lower affinity than for 5-HT2 receptor. Improves negative symptoms of psychoses and reduces incidence of extrapyramidal adverse effects.
Olanzapine (Zyprexa)
May inhibit serotonin, muscarinic and dopamine effects.
Pimozide (Orap)
Antipsychotic of the diphenylbutylpiperidine class. Used to treat delusions of parasitosis and Tourette disorder.
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