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Weight loss drugs explained

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Weight loss drugs explained

These drugs work by increasing chemicals in the brain to make us feel full and decrease our desire to consume foods.These drugs work by increasing chemicals in the brain to make us feel full and decrease our desire to consume foods.

1. Is it an option for me?

Your doctor may consider a weight-loss drug if you tick the following requirements:

  • Body Mass Index (BMI) is 30 kg/m2 or more.
  • Body Mass Index (BMI) is 27 kg/m2 or more with medical conditions that can improve with weight loss (i.e., high blood sugar levels, high blood pressure, sleep apnea).
  • Unable to lose enough weight via proper and disciplined changes to diet and lifestyle.

Download our free mini course here to calculate your BMI & learn the basics of losing excess body weight.

2. The green light

The Food & Drug Administration (FDA)has approved some drugs for short-term and long-term use.

Four prescription drugs for short-term (less than 3 months) use:

  1. Phentermine
  2. Benzphetamine
  3. Diethylpropion
  4. Phendimetrazine

These drugs work by increasing chemicals in the brain to make us feel full and decrease our desire to consume foods.

Six prescription drugs for long-term (more than 3 months) use:

  1. Orlistat (Xenical, Alli) – Reduces dietary fat absorption in the gut by blocking a fat-digesting enzyme.
  2. Phentermine-topiramate (Qsymia) – Decreases appetite & makes us feel full sooner. Suitable for individuals with migraines. Considered to be the most effective weight loss drug currently.
  3. Naltrexone-bupropion (Contrave) – Makes us feel less hungry or full sooner. Suitable for individuals with mood disorders.
  1. Liraglutide injection (Saxenda) –Mimics the hormone glucagon-like peptide-1 that targets areas of the brain that regulate appetite and food intake. Suitable for individuals with Type 2 Diabetes.
  2. Semaglutide injection (Wegovy) – Mimics a hormone called glucagon-like peptide-1 that targets areas of the brain that regulate appetite and food intake.
  3. Setmelanotide injection (IMCIVREE) – May reduce appetite, increase feeling of fullness, increase how the body burns energy. Only for individuals diagnosed with any of these 3 rare genetic conditions: 1) proopiomelanocortin deficiency, 2) proprotein convertase subtilisin/kexin type 1 deficiency & 3) leptin receptor deficiency.

Long-term is defined as taking the drugs indefinitely for as long as our health is benefiting from them and we are not experiencing serious side effects.

3. The not-so-green effects

These weight loss drug options come with their own cautions. Some common side effects include:

  • Diarrhoea
  • Leakage of oily stool
  • Constipation
  • Dizziness
  • Taste changes
  • Trouble sleeping
  • Headache
  • Increased heart rate
  • Nausea

These symptoms vary with each drug and may improve overtime. Rarely, serious side effects can occur.

4. Essential tips

It is important:

  • For your experienced doctor to thoroughly consider your medical history before prescribing the drugs.
  • To ask your doctor to explain the benefits and risks of taking the drug. Weigh out if the risks are worth the potential weight loss.
  • For close-monitoring by your doctor when you are taking the drug.
  • To read the warnings of each drug yourself and learn all you need to know about it before taking them. For example, phentermine-topiramate may cause birth defects if taken while planning for pregnancy or it may interact with other medications you are taking. Some of these drugs are also unsuitable for individuals with uncontrolled blood pressure, uncontrolled thyroid issues and severe mental health conditions.

Researchers are currently working on  identifying safer and more effective drugs to help individuals with excess body weight.

5. Do weight loss drugs (really) work?

Weight loss drugs can support weight loss provided we are:

  • a suitable candidate
  • use them correctly
  • are committed to using them regularly. Some people do regain weight when they stop taking the drugs but there are ways to limit this.
  • able to afford them as some drugs can be very expensive and unfortunately, are not always covered by insurance.
  • patient – as it takes time to see the results ( at least 3- 6 months)

On average, weight loss drugs result in modest weight loss of about 5 to 10% over a period of 6 to 12 months. However, it is helpful to note that even a modest weight loss can improve our health by reducing risk of diabetes and heart diseases.

If a weight loss drug helps us to lose at least 5% of our original weight in the first 3 to 6 months, without serious side effects, it is worthwhile continuing it. If not, trying a different weight loss drug or a change in treatment might help. As each individual and the root cause of gaining excess weight is unique, it often requires trying multiple weight loss drugs or alternative treatment modality to find the right match.

6. How about herbal weight loss pills?

Herbal weight loss pills are also designed to reduce dietary fat absorption in the gut, decrease appetite and/or increase the amount of energy used by the body. They contain ingredients such as:

  • Yerba mate (sourced from leaves and twigs of a tree in South America)
  • Cascara (dried skin from coffee cherry fruit)
  • Chitosan (fibrous compound from outer skeleton of shellfish)
  • Guarana (sourced from the seeds of a tree in South America)
  • Ephedra* (stimulant herb also called ma huang)

However, herbal pills are unregulated as they don’t require approval by authorities. It is also important to note that herbal pills are not necessarily safe because they are natural – they may still cause potential side effects. For example, ephedra* is currently banned by the FDA due to more than 10,000 reports of serious side effects. Some herbal pills may also contain hidden ingredients (such as prescription drugs) that are not listed on the label, and this is a health risk. If you are thinking of trying herbal pills, only approach credible websites and sources. It is best to check for safety alerts about herbal pills online too before consuming any and don’t forget to inform your doctor as well.

7. The take-home

  • Weight loss drugs (unfortunately) won’t magically melt away body fat.
  • Weight loss drugs support modest weight loss for some individuals. Not everyone responds the same way to any given drug.
  • Weight loss drugs work best when used as part of a comprehensive weight loss program that includes diet and lifestyle changes.
  • Speak to your weight management trained doctor or registered dietitian to learn more 😊

No content on this website should be used as a substitute for direct and individualised medical advice from a doctor or registered dietitian.

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