In the US and New Zealand, the past decade has seen tremendous growth in the marketing of prescription drugs directly to patients. The pharmaceutical industry has applied pressure in other countries to relax regulations governing such marketing although this has not yet been successful. While we still have much to learn about the potential impact on the public's health of direct-to-consumer (DTC) marketing, some data are available. This article summarises the current literature on the benefits and risks of DTC marketing. This marketing strategy has grown substantially in the US, but only select drugs are advertised. Whether there is net benefit or harm to the public's health as a result of DTC marketing depends critically on which drugs are advertised and the quality of the information provided in promotional material. Critical reviews of this promotional material suggest the information is of poor quality. Notably, 18% of the 50 drugs advertised most intensively in the US were medications used to treat psychiatric and neurological disorders. The impairments in decisional capacity often seen in psychiatric and neurological illness leave patients vunerable to the controlling influence of DTC marketing and, thus, undermine the patient autonomy that is said to be promoted by this marketing strategy. If there is any benefit from DTC marketing it is for significantly undertreated conditions. International restrictions on DTC marketing should remain in place until further evidence of net benefit or harm emerges from the DTC marketing experiment that is taking place in the US and New Zealand.