Antipsychotics Use - Typical and Atypical Medications

A Mini Lecture with Dr. Dines


Typical (classic) antipsychotics, e.g. Thorazine, Haldol
Thorazine was used initially as a BP medication, when his antipsychotic effect was discovered. Therefore, all typical antipscychotics can drop the BP.

Spectrum: Potency vs. Anticholinergic SE

Potency (upper row)

weak drug -----------------------> strong drug
dry mouth <----------------------- negligible SE

Anticholinergic effects (lower row)

Thorazine dose is 600-1000 mg QD (weak, antocholinergic SE) as compared to Haldol 5-10 mg QD (strong, high potency, low incidence of anticholinergic SE)


Atypical antipsychotics - all of them are 5-HT blocker

Seroquel
Sedating
Senile population - best choice in geriatric patients due to low incidence of anticholinergic SE and EPS

Abilify - very good choice, mixed
Antagonist
Agonist of 5-HT receptor

Risperdal is
Risky for EPS especially at high doses
To avoid EPS, start Risperdal at a very low dose in elderly, e.g. 0.5 mg QD

Olanzapine is not a good choice in
Obese patients with
OGTT abnormal - induces DM2

Zyprexa comes in a very convenient dissolvable tablet - Zyprexa MT (mouth tablet) and IM injection form, Eli Lilly covers the entire spectrum with Zyprexa - PO, MT, and IM.

Geodon
Greater QT interval - not used much

How often does a psychiatrist prescribe each drug?
Typical use of antipsychotics expressed in percentages:
30% Risperdal (potent drug even at a low dose)
30% Abilify
25% Seroquel (almost no EPS)
10% Zyprexa and Haldol