Self-medication with nutritional supplements and herbal over-thecounter products

Abstract

In recent years, the popularity increased for nutritional supplements and herbal products. Prescription drugs, but not herbal therapies are paid by health insurances. They are sold over-the-counter (OTC) on the patients’ own expense. However, there are potential risks of self-medication, e.g. incorrect self-diagnosis, severe adverse reactions, dangerous drug interactions, risk of addiction etc. They are often used by patients at their own discretion without knowledge of and control by their physicians. Certain users are at risk of intoxication. Multiple medications taken by older patients increase the risk for adverse drug reactions, drug-drug interactions, and compliance problems for this age group (polypharmacy). Herbals should be discontinued prior to operations to avoid interactions with anesthetics or anticoagulants. Herbal preparations may also be carcinogenic or interfere with cancer treatments. Pregnant women use various OTC preparations. However, in many cases, it is unclear whether their use is safe for mother or baby. Self-medication with herbals is also largely distributed among anxious and depressive patients, and patients with other conditions and symptoms. The popularity of herbal products has also brought concerns on quality, efficacy and safety. Cases of botanical misidentification, contaminations with heavy metals, pesticides, radioactivity, organic solvents, microbials as well as adulteration with chemical drugs necessitate the establishment of international quality control standards. Hepatotoxic effects have been reported for more than 300 plant species, and some commonly used herbs have been demonstrated to interact with Western medication. Health care professionals have a critical responsibility assessing the self-care ability of their patients. Databases are available for pharmacists with information on action, side effects and toxicities as well as herb-drug interactions. There is a need for established guidelines regarding the correct use of nutritional supplements and herbal OTC preparations (phytovigilance). Physicians, pharmacists, and other health care professionals have to counsel patients and the general public on the benefits and risks associated with herbal drugs. Information centers for consumers and general practitioners are needed, and convincing evidence on safety and efficacy of herbal products has to be demonstrated in placebo-controlled, double blind and randomized clinical trials.