20 Feb, 12 | by Assistant Editor
Selected items from the News and Latest Additions sections of www.palliativedrugs.com , the world’s leading palliative care website.
Citalopram and escitalopram maximum daily doses restricted
Restrictions on the maximum daily doses of citalopram and escitalopram have been made following the evaluation of a QT study by the UK Medicines and Healthcare products Regulatory Agency (MHRA). The study showed dose-dependent QT interval prolongation with citalopram and escitalopram, and post-marketing reports of prolonged QT interval have also been received. A similar decision was taken by the US Food and Drug Administration (FDA) last year (see our news item 25-08-11).
Citalopram: the maximum daily dose of citalopram is restricted to 40mg, and to 20mg in the elderly or those with hepatic impairment.
Escitalopram: the maximum daily dose of escitalopram for adults <65 years remains 20mg daily; for those >65 years, the dose has been reduced to 10mg daily.
Citalopram and escitalopram are contra-indicated in patients with known QT interval prolongation or congenital long QT syndrome and in conjunction with other products known to prolong the QT interval. These include:
- class IA and III antiarrhythmics (e.g. amiodarone, dronedarone, quinidine)
- antipsychotics (e.g. fentiazine derviatives, pimozide, haloperidol)
- tricyclic antidepressants
- some antimicrobial agents (e.g. sparfloxacin, moxifloxacin, erythromycin IV, pentamidine, antimalarial treatment, particularly halofantrine)
- some antihistamines (e.g. astemizole, mizolastine)
- some antiretrovirals (e.g. ritonavir, saquinavir, lopinavir).
Caution is advised in patients with underlying heart conditions and those at risk of low plasma levels of potassium and magnesium. Doses of citalopram and escitalopram may also need to be reduced if used in conjunction with drugs that increase their plasma levels, e.g. some antiretrovirals, omeprazole and cimetidine. For more information click here.
Reminder about fentanyl transdermal (TD) patches and heat sources
The Royal Pharmaceutical Society has issued a reminder about counselling patients regarding avoiding heat sources when using fentanyl TD patches. This follows reports in the press about the dangers of using them in the bath, with one reported fatality.
Patients using fentanyl TD patches should avoid heat sources such as hot water bottles, heat patches, electric blankets, heat lamps, hot whirlpool spa baths and prolonged hot baths, as an increase in temperature can increase the rate of absorption of fentanyl from the patch. This information is contained in the patient information leaflet. For more information click here.
This advice is echoed in our Quick Practice Guide: Use of transdermal fentanyl patches. It further advises that patients may shower but should not soak in a hot bath.
Prepared by Sarah Charlesworth and Andrew Wilcock