Fosamprenavir and Mirtazapine interaction
Fosamprenavir and Mirtazapine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
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
…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).
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)].
Antidepressant: Paroxetine, trazodone ↓ Paroxetine Any paroxetine dose adjustment should be guided by clinical effect (tolerability and efficacy). ↑ Trazodone Adverse events of nausea, dizziness, hypotension, and syncope have been observed following coadministration of trazodone and ritonavir.
Tricyclic antidepressants: Amitriptyline, imipramine ↑ Tricyclics Therapeutic concentration monitoring is recommended for tricyclic antidepressants. a See Clinical Pharmacology (12.3)
From the Mirtazapine (REMERON) label · effective 2025-08-06
Examples phenytoin, carbamazepine, rifampin Strong CYP3A Inhibitors Clinical Impact The concomitant use of strong CYP3A inhibitors with REMERON/REMERONSolTab may increase the plasma concentration of mirtazapine [see Clinical Pharmacology (12.3) ] .
Intervention Decrease the dose of REMERON/REMERONSolTab if needed with concomitant strong CYP3A inhibitor use.
Conversely, an increase in dosage of REMERON/REMERONSolTab may be needed if the CYP3A inhibitor is discontinued [see Dosage and Administration (2.5) ].
Examples itraconazole, ritonavir, nefazodone Cimetidine Clinical Impact The concomitant use of cimetidine, a CYP1A2, CYP2D6, and CYP3A inhibitor, with REMERON/REMERONSolTab may increase the plasma concentration of mirtazapine [see Clinical Pharmacology (12.3) ].
Strong CYP3A inhibitors : Dosage decrease may be needed when REMERON/REMERONSolTab is coadministered with strong CYP3A inhibitors.
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Open in the checkerNot 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.