The Lloydspharmacy Online Doctor service has run in conjunction with DrThom since 2008 and allows patients to be managed by a doctor remotely and then receive their medicines.
The service covers a range of conditions including erectile dysfunction, contraception and smoking cessation services.
Lloydspharmacy managing director Tony Page said the online doctor service had been "very successful".
In August 2009, Lloydspharmacy acquired a 33 per cent stake in DrThom. The latest acquisition gives Lloydspharmacy a 100 per cent shareholding.
Founding director of the online Dr Thom Van Every will remain with Lloydspharmacy as director of medical services as part of the agreement.
Dr Every and his wider team of doctors will continue to provide the online doctor service, Lloydspharmacy said.
Mr Page said that Lloydspharmacy plans to use its online presence to reach patients who might avoid normally seeking medical advice.
"We know there is increasing demand from customers for online healthcare; whether they feel more comfortable in an online environment or prefer the convenience over a face-to-face appointment," he said.