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Dr Michael Sandberg

Medical Director

Michael is the Medical Director of 90 Sloane Street.

He has had specialist training in internal medicine, cardiology, echocardiography and cancer medicine.

Michael is keen that the cancer care at 90 Sloane Street is of the highest level and to ensure this, he has attended the American Society of Clinical Oncology five day meeting in Chicago each year since 2016. He developed the cardiology and ultrasound programme at 90 Sloane Street. He is a Fellow of the Institute of Cancer Research and Royal Marsden Hospital.

Other Interests:
Family medicine, psychiatry and children’s healthcare.

Outside of work Michael’s passions are sailing an old wooden boat, singing and opera.

Qualified in 1983.
GMC registration number: 2846093

Email: secretary@90sloanestreet.com

Dr John Cowen


Dr John Cowen works as a private GP at 90 Sloane Street in Knightsbridge, an area where he has worked since 1978.  He read Medicine at Pembroke College, Cambridge, and then qualified at St Thomas’ Hospital in London.

He comes from a medical family going back at least four generations. He is married with children and a new grandchild and lives in Suffolk and London. He is involved in all aspects of General Practice and is hugely experienced having worked as a GP for more than 40 years.

He is happy to see patients of any age with any type of condition and is very interested in the wide and varied problems that confront a private GP.

Dr Tim Lyons


Tim completed his post-graduate specialist training in general medicine, acute medicine, oncology, haematology, elderly care, obstetrics and gynaecology. Tim has worked as a GP Trainer and medical education since 2005 and he has been in charge of our out-of-hours rota for many years. 

Paediatrics, general medicine, elderly care. 

Dr Tim Lyons is married with three children and lives in the local area. 

Qualified in 1995.

GMC registration number: 4209810

Dr Sara Kayat


Sara has developed a passion for surgical interests, sexual health, and lifestyle medicine. She also practices cosmetic medicine. She is an all-round GP and enjoys writing and advising about the everyday things, from diet, to exercise, to snoring or stress.  As a media medic, she is often found on your television screens or in health columns discussing the latest research and headlines.

Sara is an advocate of maintaining good mental health and regularly practices mindfulness and yoga. She has a keen interest in preventative medicine through lifestyle choices like exercise and nutrition. 


Sexual and reproductive health, lifestyle medicine, media medicine.

Sara enjoys extreme sports such as scuba diving, skiing, bouldering and travelling. She took part as the doctor in Channel 4’s Bear Grylls’ Celebrity Island.

Qualified in 2009.

GMC registration number: 7043430