A companion to her in this struggle was the lesser known Dr. Sophia Jex-Blake. While both are considered "outstanding" medical figures of the late 19th century, Garrett was able to obtain her credentials by way of a "side door" through a loophole in admissions at the Worshipful Society of Apothecaries. Having privately obtained a certificate in anatomy and physiology, she was admitted in 1862 by the Society of Apothecaries who, as a condition of their charter, could not legally exclude her on account of her sex. She continued her battle to qualify by studying privately with various professors, including some at the University of St Andrews, the Edinburgh Royal Maternity and the London Hospital Medical School. In 1865, she finally took her exam and obtained a licence (LSA) from the Society of Apothecaries to practise medicine, the first woman qualified in Britain to do so openly (previously there was Dr James Barry who was born and raised female but presented as male from the age of 20, and lived his adult life as a man). On the day, three out of seven candidates passed the exam, Garrett with the highest marks. The Society of Apothecaries immediately amended its regulations to prevent other women obtaining a licence  meaning that Jex-Blake however could not follow this same path; the new rule disallowed privately educated women to be eligible for examination. It was not until 1876 that the new Medical Act (39 and 40 Vict, Ch. 41) passed which allowed British medical authorities to license all qualified applicants whatever their gender. Though she was now a licentiate of the Society of Apothecaries, as a woman, Garrett could not take up a medical post in any hospital. So in late 1865, Garrett opened her own practice at 20 Upper Berkeley Street, London. At first patients were scarce, but the practice gradually grew. After six months in practice, she wished to open an outpatients dispensary, to enable poor women to obtain medical help from a qualified practitioner of their own gender. In 1865, there was an outbreak of cholera in Britain, affecting both rich and poor, and in their panic, some people forgot any prejudices they had in relation to a female physician. The first death due to cholera occurred in 1866, but by then Garrett had already opened St Mary's Dispensary for Women and Children, at 69 Seymour Place. In the first year, she tended to 3,000 new patients, who made 9,300 outpatient visits to the dispensary.