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Obalon (Weight loss system)

Obalon is the world’s first swallowable balloon for weight loss with minimal impact on daily routine. It is suitable for overweight and obese adults with a BMI of 27 or more and is intended for use in conjunction with a diet and behaviour modification programme. Treatment lasts for just 12 weeks and is performed by swallowing a capsule the size of a large vitamin pill, meaning that having an endoscopy (gastroscopy) to insert the Obalon is not required.

Up to 3 balloons are placed during the treatment period; typically these are placed on day 1, day 14 and day 28 according to patient response. Once filled with nitrogen gas, the balloons weigh only 6 grams and float comfortably at the top of the stomach, providing a feeling of fullness leading to reduced portion size and calorie intake and therefore weight loss.

Before going ahead with the Obalon procedure, a dissolvable placebo capsule is swallowed by the patient during the initial consultation with the doctor. The placebo capsule is the same size and shape as the Obalon capsule and provides confidence to swallow the real capsule. Anti-acid medication is taken for 3 days before the Obalon to reduce the build-up of stomach acid. No food is eaten 8 hours prior to swallowing the capsule, but drinking water is permitted up to 4 hours beforehand.

Some patients experience nausea and upper abdominal discomfort for a few days after receiving Obalon. To reduce these side effects, appropriate medication is provided. Eating solid foods after 24 hours also helps to eliminate these symptoms.

Throughout the 12 week treatment period, lifestyle changes and a healthy eating plan is followed to limit the intake of high calorie foods as recommended by the dietician to encourage eating behavior modification. After 12 weeks, weight loss treatment is complete. The balloons are deflated and removed during an endoscopy (gastroscopy), performed under sedation or a short acting general anaesthetic. A review appointment with the dietician and doctor will be arranged.

The multidisciplinary Obalon clinical team comprises consultant gastroenterologists, Dr Chris Fraser, Dr Gavin Johnson and Dr George Webster; consultant endocrinologist and diabetologist, Dr Mark Vanderpump; consultant psychiatrist and psychologist, Dr Yoram Inspector and senior dietician, Ms Ali Todd.

For further information and for referrals please call Dr Fraser's secretary on 020 3282 7284 or email