The investment takes the total raised by ZocDoc in its history to at least $68m, and it is also backed by Founders Fund and Khosla Ventures.

DST Global, the fund run by Russian businessman Yuri Milner, has invested $50m in medical website ZocDoc.

The investment in ZocDoc  was announced by ZocDoc chief executive Cyrus Massoumi on his company’s blog.

Massoumi said: "Transforming healthcare across the globe will be far from easy, and there is still much work to be done. But we have just taken a serious step towards this goal with the help of Yuri Milner, one of the most prolific technology investors of our time, and his team. It is with great pride that I announce that ZocDoc has secured a $50m investment from DST Global!" DST Global is backed by Chinese internet company Tencent.

He added: "Over the last four years we have seen explosive growth. When our virtual doors opened, we offered just 5,000 dentist appointments in Manhattan; today, we offer 5 million appointments across nine major metropolitan areas and dozens of medical specialties."

The company has raised at least $68m in its history. Last year ZocDoc raised $15m in its series B round which was led by Founders Fund, which includes managing partners Peter Thiel and Sean Parker, as well as venture firm Khosla Ventures. The company previously raised $3m in its Series A round led by Khosla Ventures.