Myopathies associated with red yeast rice and liquorice: spontaneous reports from the Italian Surveillance System of Natural Health Products

Many drugs can be responsible for muscle injuries.Besides statins, recognised as the drugs most commonly associated with severe myopathies, other medications such as neuroleptics, proton pump inhibitors and recently gabapentin [1] have been associated with this type of adverse drug reaction (ADR). Recent case reports have highlighted that active compounds from medicinal plants can also be responsible for myopathies [2, 3], including rhabdomyolysis but a systematic evaluation of reporting databases is still lacking. In the present study, the Italian ADR database [4, 5] of natural health products was analyzed with the aim of evaluating the possible ‘signal alarms’ due to herbal medicines and muscle injuries. A panel of experts, including a medical toxicologist, a pharmacist and a physician expert in herbal medicine reviewed all reports of myopathy to define the causality assessment using the Naranjo probability scale [6].