Buspirone

Evidence comes from outpatients resembling GAD, including coexisting depressive symptoms. Everyday stress usually does not warrant an anxiolytic. Controlled long-term efficacy beyond 3–4 weeks was not established in this label; periodically reassess continued treatment.

Take consistently with or without food. Severe renal or hepatic impairment: use cannot be recommended; exposure increases substantially and no fixed adjustment algorithm is supplied for lesser impairment. Use lower doses cautiously with strong CYP3A4 inhibitors.

Allow at least 14 days between buspirone and an antidepressant MAOI in either direction. Do not start during linezolid or IV methylene blue treatment. Urgent reversible-MAOI therapy requires clinician-directed stopping and surveillance; do not apply routine antidepressant washout rules without reviewing the exact protocol.

Hypersensitivity to buspirone; concomitant antidepressant MAOIs or use within 14 days in either direction; initiating buspirone during linezolid or IV methylene blue therapy.

The selected U.S. label has no boxed warning. Its MAOI and serotonin-syndrome restrictions still apply.

Common effects include dizziness, nausea, headache, nervousness and lightheadedness. Postmarketing allergy/angioedema and movement disorders are reported with uncertain frequency/causality. Overdose requires immediate medical assessment and supportive monitoring of breathing, pulse and BP; no specific antidote is known and dialyzability is undetermined.

• Erythromycin: label example 2.5 mg twice daily; itraconazole or nefazodone: 2.5 mg once daily, followed by individualized reassessment.
• Diltiazem/verapamil and other strong CYP3A4 inhibitors can raise exposure; review a lower dose and adverse effects.
• Rifampin and other CYP3A4 inducers may reduce benefit; reassess dosing clinically.
• Avoid large amounts of grapefruit juice; avoid tryptophan combinations. Serotonergic drugs/triptans require close observation.
• Other psychotropics require caution; haloperidol concentrations may increase and diazepam-metabolite effects have been reported.

Buspirone can produce false-positive urinary metanephrine/catecholamine results. The label directs discontinuation at least 48 hours before collection; coordinate this with the prescriber/testing team.

Adequate controlled human pregnancy studies are lacking; use only if clearly needed after individual assessment. The selected label states human milk excretion is unknown and advises avoiding use during nursing if clinically possible.

Two 6-week GAD trials in ages 6–17 did not show efficacy over placebo; long-term pediatric safety/efficacy data are absent. Older-adult experience was broadly similar to younger adults, but greater sensitivity is possible.

High 5-HT1A affinity is documented; the complete anxiolytic mechanism is unknown. Buspirone lacks benzodiazepine/GABA binding activity and does not provide typical anticonvulsant or muscle-relaxant effects.

Absorption

Rapid; peaks about 40–90 minutes after selected oral doses.

Metabolism

Extensive first pass, primarily CYP3A4; metabolites include 1-PP.

Half-life

Unchanged drug about 2–3 hours.

Disposition

Approximately 86% protein-bound; urinary/fecal metabolite elimination.

• Assess symptom response and continued treatment need.
• Review serotonergic/CYP3A4 drugs, renal/hepatic function and adverse CNS or movement symptoms.
• No specific routine laboratory tests are recommended by this label; testing follows clinical circumstances.

Take scheduled doses as prescribed and keep meal timing consistent. Avoid large grapefruit-juice intake and alcohol. Check before new medicines, pregnancy or breastfeeding. Avoid driving until effects are known; report restlessness or allergic symptoms promptly.

Appearance

White ovoid rectangular, beveled, uncoated and scored.

Imprint

B / 75 separated by score.

Packager

RemedyRepack; source NDC 59651-390.

Example NDC

70518-4317-0 · 30-tablet blister.

U.S. status

Prescription; not a controlled substance.

Source-label tablets

5, 7.5, 10, 15 and 30 mg; selected repack is 7.5 mg.

Scoring

15/30 mg source tablets are specially scored into halves/thirds; verify exact product before dividing.

Store 20–25°C; protect from temperatures above 30°C. Dispense in a tight, light-resistant container. Use the exact tablet’s splitting directions; discard incorrectly broken segments.