Paxil / Seroxat - revised SPC - reduced efficacy of tamoxifen - SSRIcrusaders post 34128

http://health.groups.yahoo.com/group/SSRI-Crusaders/message/34128


Seroxat (paroxetine) 10mg, 20mg, 30mg tablets, 20mg/10ml oral suspension - Revised SPC
Source: eMC (electronic Medicines Compendium)

http://www.nelm.nhs.uk/en/NeLM-Area/Other-Lib-Updates/SPC-Changes/Seroxat-paroxetine-10mg-20mg-30mg-tablets-20mg10ml-oral-suspension---Revised-SPC/



Date published: 06/05/2009 23:07

Type of SPC Change: Revised SPC

Generic drug name: Paroxetine

Drug brand name: Seroxat

Legal status: POM

Pharmaceutical manufacturer: Glaxosmithkline

Summary
by: No information given
Section 4.4 (special warnings and precautions for use) now states that paroxetine may lead to reduced efficacy of tamoxifen. It is recommended that prescribers consider using an alternative antidepressant with minimal CYP2D6 activity.

Section 4.5 (interactions) contains further information as follows:

Tamoxifen is a pro-drug requiring metabolic activation by CYP2D6. Inhibition of CYP2D6 by paroxetine may lead to reduced plasma concentrations of an active metabolite and hence reduced efficacy of tamoxifen, especially in extensive metabolisers. It is recommended that prescribers consider using an alternative antidepressant with minimal CYP2D6 activity.

Section 4.6 (pregnancy) has additional information which states that some epidemiological studies suggest an increased risk of congenital malformations, particularly cardiovascular (e.g. ventricular and atrial septum defects), associated with the use of paroxetine during the first trimester. The mechanism is unknown. The data suggest that the risk of having an infant with a cardiovascular defect following maternal paroxetine exposure is less than 2/100 compared with an expected rate for such defects of approximately 1/100 in the general population.

About this library entry
Category: 4.3.3 Selective serotonin re-uptake inhibitors Mood disorders (including depression)
NeLM area: Other Library Updates > SPC Changes
SPC
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