News: Current Problems in Pharmacovigilance

The Pharmaceutical Journal Vol 267 No 7163 p281-283
1 September 2001

Current Problems in Pharmacovigilance

The latest edition of Current Problems in Pharmacovigilance (2001;27:9–15) published by the Committee on Safety of Medicines and the Medicines Control Agency (and available at www.mca.gov.uk) includes the following recommendations:

High dose fluticasone warning

Product information for inhaled fluticasone (Flixotide) products is being updated to highlight the risk of systemic adverse events. The new advice includes a recommendation to titrate to the lowest effective dose. In addition, only specialists should prescribe doses above 500µg twice daily. GlaxoSmithKline said that the new advice will be included in the product information for Flixotide by the end of this year.

Cardiotoxicity with itraconazole

Caution is needed when itraconazole (Sporanox) is prescribed for patients at risk of heart failure. This is because of the possibility of itraconazole having a cardiodepressant effect (PJ, 19 May, p669).

Warning for traditional Chinese medicine

Unlicensed medicines, including traditional Chinese medicines, that contain the Psoralea corylifolia fruit should be avoided because of the risk of serious skin toxicity. The fruit contains variable levels of psoralen, which is known to cause phototoxicity. Patients treated with non-standardised herbal products are at risk of serious skin reaction.

Warning for HIV drug used as prophylaxis

Serious adverse reactions to nevirapine (Viramune) have been reported when it is used in HIV post-exposure prophylaxis. These include hepatic reactions and skin rash. Prescribers are warned that no antiretroviral agents are licensed for post-exposure prophylaxis and that the risk:benefit ratio of prolonged use of nevirapine is unfavourable. If nevirapine is used, treatment should be initiated at an appropriate low dose and liver enzymes monitored.

Longer half-life for trastuzumab Recent information has indicated that the half-life of trastuzumab (Herceptin) is approximately 25 days rather than five to six days. This means that the drug might stay in the circulation for 15 to 22 weeks after therapy ends. Anthracyclines, which are known to be associated with an increased risk of cardiotoxicity when used in combination with trastuzumab, should be avoided for up to 22 weeks after stopping trastuzumab.

The Medicines Control Agency is considering distributing the next edition of Current Problems in Pharmacovigilance with the British National Formulary.