Search
buspirone (BuSpar)
Tradename: BuSpar.
Indications:
1) generally considered drug of choice in the initial treatment of anxiety
2) especially useful for patients with history of chemical dependence - little potential for abuse
3) not for acute anxiety
Contraindications:
- avoid use in patient with hepatic or renal impairment
Caution:
1) safety not established in children < 18 years of age
2) avoid driving when initiating therapy until certain than buspirone does not adversely effect mental status
3) not for PRN use
4) does not prevent benzodiazepine withdrawals Report: changes in senses (smelling, hearing, vision)
Dosage:
1) start 5 mg PO TID (after meals)
2) increase by 5 mg every 2-3 days
3) max 60 mg/day
4) most patients respond to 15-30 mg QD
Tabs: 5 & 10 mg.
Pharmacokinetics:
1) anxiolytics effects may take several weeks
2) extensive 1st pass metabolism in the liver
-> metabolized by cyt P450 3A4
3) administration after meals increases absorption
4) age & gender do NOT affect pharmacokinetics
Advantages:
1) well tolerated
2) does not interact with alcohol or benzodiazepines
3) does not cause drug dependency
Disadvantages:
1) very slow to work (2-4 weeks)
2) not always effective
3) adverse effects
Adverse effects:
1) common (> 10%)
- dizziness, lightheadedness, headache, nausea, restlessness
2) less common (1-10%)
- drowsiness
3) uncommon (< 1%)
- chest pain, confusion, muscle weakness, tachycardia, blurred vision, dry mouth, tinnitus, insomnia, nightmares, weakness, sedation, disorientation, excitement, fever, ataxia, rash, urticaria, vomiting, diarrhea, flatulence, leukopenia, eosinophilia
4) other
- increased serum transaminases
Drug interactions:
1) MAO inhibitors in combination may cause hypertensive crisis
2) cimetidine
3) alcohol
4) highly protein-bound drugs
5) haloperidol
6) any drug that inhibits cyt P450 3A4 may increase levels of buspirone
7) any drug that induces cyt P450 3A4 may diminish levels of buspirone
Laboratory:
1) specimen: serum, plasma (EDTA)
2) methods: HPLC, RIA
Interactions
drug adverse effects (more general classes)
Related
cytochrome P450 3A4 (cytochrome P450 C3, nifedipine oxidase, P450-PCN1, NF-25, CYP3A4)
General
sedative/hypnotic (tranquilizer)
Properties
MISC-INFO: elimination route LIVER [
KIDNEY ][
1/2life 2.4 +/- 1.1 HOURS
protein-binding >95%
elimination by hemodialysis -
pregnancy-category B
safety in lactation -]
Database Correlations
PUBCHEM correlations
References
- The Pharmacological Basis of Therapeutics, 9th ed.
Gilman et al, eds. Permagon Press/McGraw Hill, 1996
- Saunders Manual of Medical Practice, Rakel (ed),
WB Saunders, Philadelphia, 1996, pg 1120
- Drug Information & Medication Formulary, Veterans Affairs,
Central California Health Care System, 1st ed., Ravnan et al
eds, 1998
- Kaiser Permanente Northern California Regional Drug
Formulary, 1998
- Clinical Guide to Laboratory Tests, 3rd ed. Teitz ed.,
W.B. Saunders, 1995