The Care Quality Commission has warned that the companies that let patients to get prescription medicines online could be risking their health.
The warning comes after investigators found two firms were putting patients at risk by failing to examine their medical history before prescribing medicines.
There were also doubts about whether its workers were sufficiently skilled or qualified to issue diagnoses and prescriptions.
The care watchdog found no processes for contacting a patient's GP, even in cases requiring monitoring or a follow-up appointment.
