Cannabis was reintroduced into British medicine in 1842 by Dr. William O’Shaughnessy, an army surgeon who had served in India. In Victorian times it was widely used for a variety of ailments, including muscle spasms, menstrual cramps, rheumatism, and the convulsions of tetanus, rabies and epilepsy; it was also used to promote uterine contractions in childbirth, and as a sedative to induce sleep. It is said to have been used by Queen Victoria against period pains: there is no actual proof of this at all, but Sir Robert Russell, for many years her personal physician, wrote extensively on cannabis, recommending it for use in dysmenorrhoea [menstrual cramps]. It was administered by mouth, not by smoking, but usually in the form of a tincture (an extract in alcohol).
“Ninth Report: Cannabis,” UK Parliament website, Nov. 11, 1998