If you’re considering taking Phentermine for weight loss then you are not alone. It regularly makes the headlines but for all the wrong reasons, as people try to get hold of it through any means possible. In this blog, we look at what this diet pill does, where you can get it, and whether there are safer alternatives to help you reach a healthy weight.

What is Phentermine?

Phentermine is an appetite suppressant that was made to help people trying to lose weight. It works by increasing the neurotransmitter levels in your brain, which makes you feel less hungry with the aim of reducing your overall calorie intake.

It’s similar in nature to amphetamines, and because of their potential to be addictive, certain amphetamines are classified as a class C drug (a controlled substance). This means there are tight restrictions on where and when Phentermine can be sold in the UK.

Where can I get Phentermine?

Phentermine is not an NHS-approved drug and is not in the prescribing guidelines used by GPs, so you are unlikely to get it from your local doctor.

However the manufacturers may supply the drug to certain private slimming clinics.

Is there a safe alternative?

The only diet pill approved by the NHS is Orlistat (Xenical). It’s used by doctors and private pharmacists to treat obesity in patients with a body mass index (BMI) of:

  • Over 30
  • Over 28, and either high blood pressure, high cholesterol, or type 2 diabetes

Prescribed medications for weight loss are only given to patients who have tried to lose weight naturally by dieting and regularly exercising. Orlistat should be used as part of an overall weight loss management plan and is only prescribed for a limited time.

How does Orlistat (Xenical) work?

Orlistat – also sold under the brand name, Xenical – works by inhibiting the enzymes that break down fat in the body. By blocking these enzymes, known as lipases, Orlistat can stop up to 30% of the fat you eat from being absorbed. The undigested fat then travels through your gastrointestinal system and leaves your body as waste.

For it to be effective, Orlistat must be used as part of a calorie-controlled diet. To ensure you get the right absorption balance, the meals you eat should only contain around 30% fat. So, if your dinner is 1000 calories then roughly 300 of these should come from fat.

Orlistat isn’t intended to be used for long periods of time. If you haven’t lost at least 5% of your body weight after 12 weeks, then your GP or pharmacist will recommend you try an alternative weight loss treatment that is better suited to you.

prescribed Phentermine in the UK

Is Orlistat available over the counter?

Orlistat 120mg capsules can only be prescribed by a doctor or a private pharmacist; it cannot be bought off-the-shelf in supermarkets or chemists. You can also buy it online from a pharmacy, like Post My Meds, which is registered with the General Pharmaceutical Council.

If you’re considering buying Orlistat online, we recommend using a regulated pharmacy. Their trained healthcare professionals will ask you about your health and any other medications you are currently taking to make sure it’s safe for you to take Orlistat.

Always read the patient information leaflet that comes with your medicine – it has a full list of side effects and cautions, and explains in detail how to take Orlistat.

Phentermine versus Orlistat

Phentermine is available from private slimming clinics, but there are doubts over whether it is safe and effective. The only NHS-approved weight loss pill is Orlistat, which has been proven to work as part of a weight loss management plan.

Doctors and pharmacists will only prescribe Orlistat if a patient has tried to lose weight naturally by reducing their calorie intake and increasing physical activity. If you’ve tried unsuccessfully to lose weight and you are looking for a safe diet pill that can help, speak to the pharmacy team at Post My Meds about the benefits of using Orlistat.

Although all of our content is written and reviewed by healthcare professionals, it should not be substituted for or used as medical advice. If you have any questions about your health, please speak to your doctor.

Authored Nov 03, 2021 by Joseph Issac, MPharm
Reviewed Oct 29, 2021 by Prabjeet Saundh, MPharm