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BUSPIRONE HYDROCHLORIDE

Medical Diagnosis and Drugs, Medications
BUSPIRONE HYDROCHLORIDE
(byoo-spye'rone)
BuSpar
Classifications: anxiolytic;
Therapeutic: antianxiety
Prototype: Lorazepam
Pregnancy Category: B

Availability

5 mg, 10 mg, 15 mg tablets

Action

An anxiolytic that focuses mainly on the brain D2-dopamine receptors. It has agonist effects on presynaptic dopamine receptors and also a high affinity for serotonin (5-HT1A) receptors.

Therapeutic Effect

Antianxiety effect is due to serotonin reuptake inhibition and agonist effects on dopamine receptors of the brain.

Uses

Management of anxiety disorders and for short-term treatment of generalized anxiety.

Unlabeled Uses

Adjuvant for nicotine withdrawal, premenstrual syndrome.

Contraindications

Concomitant use of alcohol and buspirone; concomitant use of MAOI therapy. Safety during labor and delivery, lactation, or in children <18 y is not established.

Cautious Use

Moderate to severe renal or hepatic impairment, pregnancy (category B).

Route & Dosage

Anxiety
Adult: PO 7.5–15 mg/d in divided doses, may increase by 5 mg/d q2–3d as needed (max: 60 mg/d)
Geriatric: PO 5 mg b.i.d., may increase to max 60 mg/d

Administration

Oral
  • Give with food to decrease nausea.
  • Give 8 h before or after drinking grapefruit juice.
  • Store at 15°–30° C (59°–86° F) in tightly closed container unless otherwise directed.

Adverse Effects (≥1%)

CNS: Numbness, paresthesia, tremors, dizziness, headache, nervousness, drowsiness, light-headedness, dream disturbances, decreased concentration, excitement, mood changes. CV: Tachycardia, palpitation. Special Senses: Blurred vision. GI: Nausea, vomiting, dry mouth, abdominal/gastric distress, diarrhea, constipation. Urogenital: Urinary frequency, hesitancy. Musculoskeletal: Arthralgias. Respiratory: Hyperventilation, shortness of breath. Skin: Rash, edema, pruritus, flushing, easy bruising, hair loss, dry skin. Other: Fatigue, weakness.

Diagnostic Test Interference

Buspirone may increase serum concentrations of hepatic aminotransferases (ALT, AST).

Interactions

Drug: May cause hypertension with mao inhibitors, trazodone, possible increase in liver transaminases; increased haloperidol serum levels. Food: Grapefruit juice may increase drug levels. Herbal: St. John's wort may increase drug levels.

Pharmacokinetics

Absorption: Readily from GI tract, undergoes first pass metabolism. Onset: 5–7 d. Peak: 1 h. Metabolism: In liver. Elimination: 30–63% in urine as metabolites within 24 h. Half-Life: 2–4 h.

Nursing Implications

Assessment & Drug Effects

  • Monitor for therapeutic effectiveness. Desired response may begin within 7–10 d; however, optimal results take 3–4 wk. Reinforce the importance of continuing treatment to patient.
  • Benzodiazepines or sedative-hypnotic drugs are withdrawn gradually before buspirone therapy is started. Observe patient for rebound symptoms, which may occur over varying time periods during first phase of treatment.
  • Monitor for and report dystonia, motor restlessness, and involuntary repetitious movement of facial or cervical muscle.
  • Observe for and report swollen ankles, decreased urinary output, changes in voiding pattern, jaundice, itching, nausea, or vomiting.

Patient & Family Education

  • Take exactly as prescribed: Specifically, do not omit, skip, increase or decrease doses without advice of the physician.
  • Report any of the following immediately: Involuntary, repetitive movements of face or neck; weakness, nervousness, nightmares, headache, or blurred vision; depression or thoughts of suicide.
  • Do not use OTC drugs without advice of the physician while taking buspirone.
  • Note: Adverse effects subside during continued therapy with or without dosage adjustment. Do not discontinue therapy.
  • Do not drive or engage in other potentially hazardous activities until response to drug is known.
  • Alert physician if you become pregnant; buspirone must be discontinued during pregnancy.
  • Discuss limits of alcohol intake with physician; cautious use is generally advised.
  • Note: It is important to understand the planned schedule for changes in doses and intervals to ensure low incidence of withdrawal or rebound symptoms when therapy is discontinued.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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