Risk of mixing herbal remedies

AN estimated 1.3 million older Britons may be putting themselves at risk by taking alternative therapies which could potentially interact with their prescribed drugs, a study claims.

GPs should ask their patients about herbal and supplement usage to identify potential side effects, according to the authors of a study published in the British Journal of General Practice.

Researchers polled 155 people over the age of 65 who were taking at least one prescription drug.

One in three (33.6 per cent) were found to also be taking herbal medicinal products or dietary supplements alongside their prescription medicine. These patients took between one and eight additional products, with women more likely to take them than men. The most commonly used dietary supplements were cod liver oil, glucosamine, multivitamins and vitamin D.

Common herbal medicinal products being taken included evening primrose oil, valerian, and a branded herbal product that includes hops, gentian, and passion flower.

Researchers from the University of Hertfordshire identified that 16 participants were at risk of potential adverse drug interactions.

The potential side effects of interactions can include reducing the effectiveness of the prescription medication, risk of bleeding and increased blood glucose concentrations. “One-third of older adults in this study’s sample were using an herbal medicinal product or supplement concurrently with prescribed prescription drugs,” the authors wrote.

“About one in three concurrent users was at risk of a potential herb-drug or supplement-drug interaction.

“If applied to the UK population, that would mean 1.3 million older adults in the UK are at risk of at least one potential herb-drug or supplement-drug interaction.”

They added: “GPs should routinely ask questions regarding herbal and supplement use, to identify and manage older adults at potential risk of adverse drug interactions.”