Drug giant Eli Lilly has been accused of sending out free samples of the antidepressant Prozac (fluoxetine) through the post to former patients, even though they were no longer being prescribed the drug. One case, involving a 59-year-old woman in Florida, is being investigated as a possible violation of state law.

Subpoenas have been issued to the drug company, the pharmacy that sent the letter and members of a medical group who signed it.

The letter to the woman began: 'We are very excited to be able to offer you a more convenient way to take your antidepressant medication . . . For your convenience, enclosed you will find a FREE one-month trial of Prozac Weekly. If you wish to try Prozac Weekly, stop your daily antidepressant before starting, then take only Prozac Weekly once a week thereafter.'

The letter, and free sample, is a violation of the doctor-patient relationship, as cardiologist David Pearle, from Georgetown University in Washington, pointed out. 'The letter has a doctor’s signature, yet this clearly did not arise from a doctor-patient relationship. And the fact that they would enclose a sample of the drug - which could be taken by children, or sit in the home and be used after the expiration date or after a recall - is appalling in every respect.'

A spokesman for the US National Association of Chain Drugstores said that 'pharmacies do take money from drug companies to send out letters or make calls to patients to remind them that their prescriptions need to be filled or, if they have a particular condition, to let them know that there may be another drug out there that could work better. But they are not in the practice of filling prescriptions without a doctor’s consent. In any case, a free sample of the product definitely should not have gone out. We’re not dealing with a new laundry detergent here' (Lancet, 2002; 360: 234).