Ask Your Pharmacist

Question:

How do the slimming pills available over-the-counter differ from the medication that is available at the pharmacy? What medications are available to treat obesity?

Answer:

The Health Promotion Board’s definition of healthy weight is a Body-Mass Index (BMI) of 18.5 – 22.9 (to avoid risk of heart disease). A BMI of 23 – 27.4  indicates that a person is overweight while obesity is defined as having a BMI of above 27.4. The BMI is calculated by weight (kg) divided by height squared (m²).

Regarding herbal supplements for slimming, they claim to work in many ways that may or may not have clinical evidence to support them. These include thermogenic methods (raising the body’s temperature to burn calories), mimicking insulin to enhance sugar metabolism, prevention of fat absorption, detoxification and reducing sugar cravings. Most contain ingredients extracted from nature such as plants or marine-life.  Low-calorie meal replacements are also available on the market for weight-loss. As these slimming aids are not without side effects and may have conditions which disallow their use, it is best to consult a health professional before you purchase them.  

Meanwhile, use of weight control medication is recommended for people with BMI above 30 or those with BMI above 28 with 2 or more obesity-related conditions. It must always be accompanied with lifestyle changes such as diet and exercise. Appetite suppressants are available upon prescription from a doctor while at absorption altering medication are recently available as Pharmacy-Only.

Appetite Suppressants

Appetite Suppressants such as Phentermine and Sibutramine decrease the appetite by increasing chemicals found in the brain, which affects mood and appetite. Side effects may include dry mouth, inability to sleep, and constipation. These medicines are only available with a prescription.

Fat absorption-altering Medication

Orlistat blocks around 30% of fat intake from being absorbed by preventing the action of lipase, (an enzyme that break down fat).  They cause side effects such as stomach cramps, gas, diarrhoea, faecal incontinence and oily stools. They are available from a pharmacist to patients who have BMI>30, with no medical conditions and are not on long-term medications.

A pharmacist is skilled in providing counseling for patients on this medication on how to take the medicine to maximise effectiveness, manage side effects as well as provide advice on healthy lifestyle practices pertaining to lifestyle and diet. He and she can confirm a BMI measurement, take down a patient’s history and tailor a dietary and exercise regime and/ or drug regimen to help in weight loss.

Source: Choong Wei Sim, Pharmacist, Pharmaceutical Society of Singapore

More information and advice can be obtained from your pharmacist. Send your questions to sthealth@sph.com.sg

References:

1. American Obesity Association  http://www.obesity.org/subs/fastfacts/Obesity_Treatment.shtml

2. Health Promotion Board

 http://www.hpb.gov.sg/hpb/default.asp?pg_id=865&aid=266