Which medicines work best to help you lose weight?

Even though some medicines may help us lose weight, it is not the only way to achieve your ideal weight – “Lifestyle” choices (diet and exercise) go a long way to maintain a healthy weight, body and mind!

And by the way, low fat, low sugar, high carb, high fat, high protein diets usually only work short term and do not provide long term healthy eating options!
Nonetheless, we may need some help for the weight loss journey and there are some medicines which can give us the kickstart that we need.
But first things, first – some medicines can cause weight gain and these need to be identified first before using any weight loss prescription medicines;

1. Insulin and sulfonylureas are necessary to manage diabetes, so this is a special case which needs careful guidance with your doctor and pharmacist.
2. Steroid hormones like prednisone and some birth control injections (Depo-Provera)
3. Some antidepressant medicines like amitriptyline, paroxetine, citalopram, mirtazapine, and sertraline may also put on weight – if unsure, check with your doctor or pharmacist.
4. Epilepsy and blood pressure medicines can also cause weight gain and may require specialist advice for any changes here also.

There are three groups of medicines that are commonly used for the management of obesity – that’s where we may have a BMI of 30 kg/m2 or more.

Group one – Gastrointestinal agents

a. Orlistat (Xenical) reduces weight by decreasing the dietary absorption of fat – this drug is known as a gastrointestinal and pancreatic lipase inhibitor, and is available over the counter, without prescription. Unfortunately, this drug can cause adverse side effects such as flatulence, oily stool, and diarrhoea because many people think they can consume more fat because the drug will prevent it from being absorbed. In addition, orlistat may reduce absorption of fat soluble vitamins such as A,D, E , and K with the latter being a problem for patients taking warfarin.
b. High fibre supplements also make the stomach feel full and can reduce the total calorie intake which may lead to weight loss. It is important to drink lots of fluid with these fibre supplements to prevent constipation and bowel blockage.

Group Two – Stimulant drugs working on the brain

a. These work best with calorie controlled diet.
b. Are usually prescribed for patients with BMI of 30 kg/m2 or more.
c. Phentermine (Duromine) is recommended as an add on treatment with lifestyle modification for short term use only – three months, usually. The starting dose is usually 30mg daily and it may cause adverse side effects such as high blood pressure palpitations, restlessness, insomnia, dizziness, overstimulation, nausea, abdominal cramps and dry mouth.
d. ContraveR is a newer drug combination of Naltrexone and Bupropion which is thought to act on the dopamine reward system to regulate appetite. The usual starting dose is one tablet in the morning with gradual increase to two tablets twice daily. Weight loss may be up to 4-5 kg which seems to plateau after 6 months and there is not enough data for its use beyond 12 months. Common adverse side effects (less than 1% of patients) may include sweating, hot flush, dizziness, dysgeusia (lack of taste), nervousness, lethargy, tinnitus, nausea, constipation, Importantly, this drug may not be given to people taking opioid analgesics as naltrexone will antagonise the action of these drugs and cause withdrawal symptoms.

Group Three – Glucagonlike peptide-1 Agonists

a. These include drugs like Semaglutide (Ozempic), Exenatide (Byetta), and Dulaglutide (Trulicity) which have been prescribed for weight loss but were originally designed for to control high blood sugar levels in people with diabetes. Recently, the overuse of these drugs has led to shortages of these vital medicines for the management of diabetes with the therapeutic Goods Administration and the Australian Medical Association now recommending that these drugs be limited to its approved use only (diabetes) and not weight loss.
b. Liraglutide (Saxenda) is approved for weight loss and may produce weight loss by up to 5% after 12 weeks but requires daily injections which may be inconvenient for some patients – adverse side effects may include nausea, diarrhoea, constipation, vomiting, dyspepsia and dizziness,
Whilst there are some medicines that may help you lose weight, there is one thing that is certain – Obesity is a major health problem and the best thing that you can do for yourself is to make a start.
Importantly, talk to your doctor or pharmacist about the safest way to do it.

Emmanuel Pippos, Consultant Pharmacist.

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1. Download and print the form.
2. Tick the boxes that you think may affect you.
3. Then make an appointment with your doctor.


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