Little is known about Peter Lowe's early life. He seems to have been born in Scotland, probably in Ayr, and gone to Europe in search of his education. He subsequently practised in France and Flanders. By 1589 he was chirurgian (surgeon) major to the Spanish Regiment in the service of Philip II, the King of Spain, at the siege of Paris. In the early 1590s he travelled in England with Alexander Dickson, the secretary to the Earl of Errol, who like his master was a Catholic. While there he surveyed several harbours, sending details back to James VI in Scotland. On his return to France he was appointed chirurgian ordinary to Henry IV, the Most Christian King of France and Navarre in about 1595.
He went to London in 1596 when he published a book on the cure and prevention of the "Spanish sickness", which was followed in 1597 by a general treatise on surgery. He was in Glasgow by 1598 and received a charter from James VI to establish what was to become the Royal College of Physicians and Surgeons the following year. In the charter he is described as "our Chirugiane and Chief Chirugiane to oure dearest son the Prince", Prince Henry, who died in 1612. His practice seems to have covered much of south-west Scotland. He was in Ayr in 1600 when he treated the wounds of the Laird of Bargany. A contemporary account recorded he "had na skill, bot laid plaisteris (plasters) to the wondis (wounds)" and the patient died.
This did not prevent him being despatched by James VI in 1601 to accompany the Earl of Lennox on a mission to King Henry's court in Paris. In Glasgow he married as his second wife, Helen Wemyss, the daughter of the first Protestant minister of the Cathedral. He died in 1610 and is buried in the Cathedral where his tomb can still be seen.