Doctors' prescription behaviour regarding dosage recommendations for preparations of kava extracts

There are many publications on the use of kava extracts as a treatment alternative to tricyclic antidepressants and benzodiazepines, but little has been done to investigate the potential adverse effects that may be associated with prolonged or high-dose usage.

To investigate the extent to which physicians comply with the recommended daily dose (RDD) of an antidepressant such as kava and the consequences of this behaviour with regard to the safety and efficacy of frequently prescribed kava extracts (Trade names: Antares, Laitan and Kavasporal forte).

The analysis was carried out using the patient database MediPlus, which provides anonymous access to a representative and valid panel of physicians and patients in Germany.

Prescriptions for Antares showed that the RDD of 1 tablet per day was exceeded in 58.2% of the cases, while those for Laitan showed that the RDD of 1 capsule per day was significantly exceeded in 75.6% of the cases; a one-off prescription was issued in 66% of the cases. As a result, the required effect diminished very quickly. Prescriptions for Kavasporal forte showed that the daily dosage of 2 capsules per day complied with the recommendations in only 49.1% of the cases; in 38.8% of the cases, the dosage dropped below the respective recommendation. As a consequence, the lower-dosed Kavasporal forte was prescribed for longer periods than the higher-dosed Antares and Laitan.

In the case of a low-dosage recommendation, we saw a trend to over-dose in prescribing behaviour, which increases the risk of undesirable adverse reactions. On the other hand, we saw a trend to under-dose in the case of a higher dosage recommendation. This fact may explain the unexpected inefficacy of the therapy. These trends affected the duration of therapy, whereby a dosage lower than the RDD was prescribed for a longer period than a dosage higher than the RDD.