General

Pronunciation
byoo-SPYE-rone

Trade Name(s)

• BuSpar

Pregnancy Category
Category B

Ther. class.
antianxiety agents

Indications

Management of anxiety

Action

• Binds to serotonin and dopamine receptors in the brain

• Increases norepinephrine metabolism in the brain

Therapeutic Effect(s):
Relief of anxiety

Pharmacokinetics

Absorption: Rapidly absorbed

Distribution: Unknown

Protein Binding: 95% bound to plasma proteins

Metabolism and Excretion: Extensively metabolized by the liver (CYP3A4 enzyme system); 20–40% excreted in feces

Half-life: 2–3 hr

TIME/ACTION PROFILE (relief of anxiety)

ROUTE	ONSET	PEAK	DURATION
PO	7–10 days	3–4 wk	unknown

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity

• Severe hepatic or renal impairment

• Concurrent use of MAO inhibitors

• Ingestion of large amounts of grapefruit juice

Use Cautiously in:

• Patients receiving other antianxiety agents (other agents should be slowly withdrawn to prevent withdrawal or rebound phenomenon)

• Patients receiving other psychotropics

• Lactation: /OB: /Safety not established

Adverse Reactions/Side Effects

CNS: dizziness, drowsiness, excitement, fatigue, headache, insomnia, nervousness, weakness, personality changes.

EENT: blurred vision, nasal congestion, sore throat, tinnitus, altered taste or smell, conjunctivitis.

Resp: chest congestion, hyperventilation, shortness of breath.

CV: chest pain, palpitations, tachycardia, hypertension, hypotension, syncope.

GI: nausea, abdominal pain, constipation, diarrhea, dry mouth, vomiting.

GU: changes in libido, dysuria, urinary frequency, urinary hesitancy.

Derm: rashes, alopecia, blisters, dry skin, easy bruising, edema, flushing, pruritus.

Endo: irregular menses.

MS: myalgia.

Neuro: incoordination, numbness, paresthesia, tremor.

Misc: clamminess, sweating, fever.

*CAPITALS indicates life-threatening.
*italic indicates most frequent.

Interactions

Drug-Drug

• Use with MAO inhibitors may result in hypertension and is not recommended

• Erythromycin, nefazodone, ketoconazole, itraconazole, ritonavir , and other inhibitors of CYP3A4 blood levels and effects of buspirone; dose reduction is recommended (decrease to 2.5 mg twice daily with erythromycin, decrease to 2.5 mg once daily with nefazodone)

• Rifampin, dexamethasone, phenytoin, phenobarbital, carbamazepine, and other inducers of CYP3A4 blood levels and effects of buspirone; dose adjustment may be necessary

• Avoid concurrent use with alcohol

Drug-Natural Products
Concomitant use of kava, valerian, or chamomile can CNS depression

Drug-Food
Grapefruit juice serum levels and effect; ingestion of large amounts of grapefruit juice is not recommended

Route/Dosage

• PO (Adults): 7.5 mg twice daily; increase by 5 mg/day q 2–4 days as needed (not to exceed 60 mg/day). Usual dose is 20–30 mg/day (in 2 divided doses).

Availability

• Tablets: 5 mg, 7.5 mg, 10 mg, 15 mg, 30 mg

» Cost:
Generic: 5 mg $79.97/180, 7.5 mg $110.97/180, 10 mg $128.99/180, 15 mg $129.40/180, 30 mg $267.93/180.

Assessment

• Assess degree and manifestations of anxiety before and periodically during therapy

• Buspirone does not appear to cause physical or psychological dependence or tolerance. However, patients with a history of drug abuse should be assessed for tolerance or dependence. Restrict amount of drug available to these patients

Potential Nursing Diagnoses

• Anxiety (Indications)

• Risk for injury (Side Effects)

Implementation

• Do not confuse buspirone with bupropion

» Patients changing from other antianxiety agents should receive gradually decreasing doses. Buspirone will not prevent withdrawal symptoms

• PO: May be administered with food to minimize gastric irritation. Food slows but does not alter extent of absorption

Patient/Family Teaching

• Instruct patient to take buspirone exactly as directed. Take missed doses as soon as possible if not just before next dose; do not double doses. Do not take more than amount prescribed

• May cause dizziness or drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to the medication is known

• Advise patient to avoid concurrent use of alcohol or other CNS depressants

• Advise patient to consult health care professional before taking OTC medications or herbal products with this drug

• Instruct patient to notify health care professional if any chronic abnormal movements occur (dystonia, motor restlessness, involuntary movements of facial or cervical muscles) or if pregnancy is suspected

• Emphasize the importance of follow-up exams to determine effectiveness of medication

Evaluation/Desired Outcomes

Increase in sense of well-being

» Decrease in subjective feelings of anxiety. Some improvement may be seen in 7–10 days. Optimal results take 3–4 wk of therapy. Buspirone is usually used for short-term therapy (3–4 wk). If prescribed for long-term therapy, efficacy should be periodically assessed

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