1. CASE 5
Block 5
Gabatino-Labra

2. CASE 5
45 year old
50 kg
male
referred for increased sleeping hours and when awake would complain of dizzy spells.

3. Patient is a known schizophrenic maintained on Chlorpromazine
100 mg per orem 2x/day for 6 months.
Two weeks prior to consult, he was prescribed Propranolol
40 mg/tablet 2 tablets 3x/day.

4. What caused the symptoms of the patient?
QUESTION
What caused the symptoms of the patient?

5. Chlorpromazine
Psychotic Disorders
Increase dosage gradually until symptoms are controlled.
Daily dosage of 200 mg is not unusual
Side Effect: Drowsiness

6. Metabolism Chlorpromazine
typically degraded by the liver by the action of cytochrome-P450 family enzymes, usually CYP2D6
CYP 2D6
7-hydroxylation

7. Propranolol
Hypertension
40 mg Inderal twice daily as usual dose
Side effects on the Central Nervous System: depression & lassitude

8. Metabolism Propranolol
CYP 2D6
aromatic hydroxylation
4-hydroxy propranolol is a weak inhibitor of CYP2D6

9. 70% Drug Interaction Propranolol Chlorpromazine
Chlorpromazine + propranolol
Sleepiness and dizziness

10. Drug Interaction