Paroxetine is an SSRI used for depression, social anxiety disorder, OCD, and panic disorder.
Also known as: paroxetine, paxil, seroxat
CYP2D6 inhibitor SSRI + anti-hormonal: paroxetine reduces tamoxifen activity 60-80%.
Tamoxifen is activated by CYP2D6 to endoxifen. Paroxetine inhibits CYP2D6, reducing endoxifen formation 60-80%.
Compromised anti-tumoral efficacy.
Tumour growth.
CONTRAINDICATED. Switch to citalopram or escitalopram.
DailyMed/FDA; EMC-EMC PT
Paroxetine, a potent CYP2D6 inhibitor, markedly increases imipramine levels with a high toxicity risk.
Potent CYP2D6 inhibition by paroxetine reduces imipramine clearance.
ECG, confusion, tremor, urinary retention.
Dry mouth, palpitations, delirium, seizures.
Avoid the combination; if necessary, markedly reduce the TCA dose and monitor ECG and neurological status.
DailyMed — Tofranil (imipramine) label; INFARMED Prontuário Terapêutico, imipramine entry (CYP2D6 interactions): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=649837df-147f-436c-9553-32ffecf4c6f1
Alcohol potentiates sedation and may worsen cognitive effects; paroxetine (SSRI) adds CNS depression.
Avoid or strongly moderate alcohol, especially at treatment start.
EMC-UK — Paroxetine SmPC 4.5/4.7 (alcohol); site monograph.
No documented disease interactions.
No documented pregnancy or breastfeeding information.
Clinical and educational support tool. The information does not replace a medical prescription or the opinion of a qualified healthcare professional.
SSRI with highest SERT affinity. More anticholinergic effect than other SSRIs.
Potent serotonin reuptake inhibition (SERT). Anticholinergic effect (dry mouth, urinary retention). Inhibits CYP2D6.
Oral absorption. Bioavailability: 50%. Peak: 5-8 h.
Metabolised by CYP2D6 (polymorphic). Extensive first-pass metabolism.
21 h.
Medicines from the same therapeutic group (ATC classification) or the same pharmacological class.
