Fosamprenavir and Zonisamide interaction

Fosamprenavir and Zonisamide: the Fosamprenavir prescribing label flags this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.

Major

Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.

What the FDA labels say

From the Fosamprenavir (Fosamprenavir Calcium) label · effective 2026-06-30

Major

…Hypericum perforatum ) Lipid modifying agents: Lomitapide, lovastatin, simvastatin Non-nucleoside reverse transcriptase inhibitor: Delavirdine PDE5 inhibitor: Sildenafil (Revatio) (for treatment of pulmonary arterial hypertension) Sedative/hypnotics: Midazolam, triazolam Hypersensitivity to fosamprenavir calcium or amprenavir (e.g., Stevens-Johnson syndrome).

Contraindicationsby drug classView label on DailyMed
Major

Fosamprenavir calcium/ritonavir: ↔ Amprenavir ↔ Esomeprazole Sedative/hypnotics: Midazolam, triazolam ↑Midazolam ↑Triazolam Coadministration is contraindicated due to potential for serious and/or life-threatening reactions such as prolonged or increased sedation or respiratory depression [see Contraindications (4)].

Drug interactionsby drug classView label on DailyMed
Moderate

Fosamprenavir calcium should be used with caution in patients with a known sulfonamide allergy.

Warnings and precautionsby drug classView label on DailyMed
Moderate

Sulfa Allergy Fosamprenavir calcium should be used with caution in patients with a known sulfonamide allergy.

Warnings and precautionsby drug classView label on DailyMed
Moderate

In 2 clinical trials of fosamprenavir calcium plus low-dose ritonavir, rash occurred in 8 of 50 subjects (16%) with a history of sulfonamide allergy compared with 50 of 412 subjects (12%) with no history of sulfonamide allergy.

Warnings and precautionsby drug classView label on DailyMed

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Not medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.