With obesity becoming an ever more relevant and widespread problem throughout the developed world, it comes as no surprise that there is a wide range of supplements, remedies and medicines that are advertised as miracle cures. Sadly, however, there is no ‘magic pill’ that can facilitate quick, safe and clinically proven results without significant changes to the lifestyle of an individual, most importantly diet regiment and exercise programme.
What’s on this page?
When it comes to diet pills, their questionable safety has made the headlines in the UK more than once. In fact, two very popular prescription medications, namely Rimonabant (Acomplia) and Sibutramine (Reductil) have been withdrawn in the United Kingdom back in 2008 and 2010, respectively, following detailed studies that confirmed their dangerous side effects which significantly outweigh the potential benefits according to the experts and relevant public health authorities. The examples of these two medicines go on to highlight a very dangerous trend in unlicensed diet pills – their capacity to induce serious illnesses, health complications and even lethal outcome in certain cases.
In this article, we will discuss potential side effects of both prescription-only slimming pills which can be obtained at private slimming clinics and over-the-counter solutions commonly purchased in the UK.
Of course, what follows is not a comprehensive list of all known side effects. It is important to note straight away that if you do decide to purchase and use some of the medications covered here, you should definitely first thoroughly read through the official patient information leaflet that is issued within every pack of the medicine. There you will find a list of all side effects documented so far. However, keep in mind that some of these medicines are still closely monitored for currently undiscovered side effects, so even the official information might be incomplete.
Orlistat: The only approved prescription weight loss medication
As of now, there is only one prescription treatment licensed for weight loss in the UK, Orlistat. This also includes Orlistat’s branded version Xenical and lower-concentration OTC solution called Alli. The shared active ingredient of all three medicines works directly in the gut by inhibiting the activity of the specialised enzymes tasked with absorbing fat from the food in the digestive tract. The studies conducted to assess the efficacy of orlistat-based medications confirmed that these diet pills manage to cut the total fat intake by as much as third. The fat not absorbed will be excreted in faecal matter.
Both Xenical and generic Orlistat can be prescribed only to patients who have a body mass index (BMI for short) of at least 30kg/m2 or 20kg/m2, but with high risk of obesity-related conditions such as hypertension or type 2 diabetes. Both medicines are intended to be used in parallel to a comprehensive weight loss programme including strict diet and regular exercise. As such, they are prescribed in those situations where these measures fail to achieve the desired results.
As mentioned, Alli is another orlistat-based medication which can be obtained over the counter in the UK due to its lower concentration of the active ingredient.
The side effects associated with the use of orlistat-based medications tend to mostly affect the digestive system and are considered to be generally mild, albeit slightly uncomfortable. Side effects most commonly manifest early in the treatment course, subsiding afterwards as long as the user avoids meals rich in fats. Most commonly they include:
- Pain in the abdomen
- Frequent and urgent defecations
- Flatulence with discharge in some cases
- Oily and soft stools
- Pain in the rectum
Other side effects that might manifest but which do not affect the gastrointestinal tract include:
- Menstrual cycle disruption
- Low blood sugar (especially in users affect by type 2 diabetes)
- Disorders affecting the teeth and gums
In addition to this, users with acute kidney conditions are at a significantly higher risk of renal stones, while women using oral contraceptives might be at risk of unwanted pregnancy since the active ingredient of the pills might be expedited from the body during diarrhoea episodes.
Some users have also reported side effects including hepatitis, pancreatitis, rectal bleeding, diverticulitis and raised levels of liver enzymes, but so far, there is not enough information on this topic for any conclusive judgements.
Mysimba: The newest addition to the UK markets
The most recent weight loss medication to receive approval for use across the European Union and the UK is Mysimba, a combination treatment based on Bupropion and Naltrexone with both of these substances being used separately to treat various addictions. This fact alone already gives us some hints regarding the mechanism of action of Mysimba.
Bupropion acts by increasing the dopamine levels in the brain, thus contributing to the feeling of having more energy and reducing appetite at the same time. On the other hand, Naltrexone is highly efficient in maintaining the achieved weight loss and reducing cravings by interfering with the subjective experience of taste.
Mysimba is one of medications that are still being researched and monitored so the side effects identified so far don’t necessarily have to cover all possible side effects. Some of the most common include:
- Disruption of sleep patterns
- Difficulty concentrating
- Heart palpitations
- Muscle pain
- General malaise
Despite the fact that it is still being actively researched, Mysimba was approved for sale in the UK during the year 2017, so it can be obtained from the GPhC-registered pharmacies with a valid prescription.
Phentermine and Diethylpropion (unregulated slimming pills)
Both Phentermine and Diethylpropion are classified as appetite suppressants and while they are technically legal within the UK, they are not approved for weight loss, so they cannot be obtained with a prescription for that specific issue. Both medications act by stimulating the nervous system and decreasing the subjectively perceived sensation of hunger. Both belong to the same broad category of pharmaceutical companies called amphetamines. Due to this fact, these medications are on the very margins of legality, with a short period when they were completely illegal.
On top of this, both Phentermine and Diethylpropion can lead to habit formation as well as various hypertension problems and diseases of the cardiovascular system.
The side effects of these medications include, but are not limited to:
- Difficulty sleeping
- Mood swings
- Dryness of the mouth
- Unpleasant taste in the mouth
As these drugs aren’t approved for weight loss by the relevant authorities and can be potentially dangerous, we strongly advise you not to use them.
Herbal weight loss medicines
Anyone who tried to gather some information regarding weight loss medications certainly knows very well that there is a wide array of herbal treatments and medications available on every corner, with some of them being accompanied by celebrity endorsements, pricey and professional advertising campaigns and outrageous claims of incredible results.
Some of them are presented as traditional herbal remedies, known to the wise old men and women form the ye old days, while others are represented as state of the art medical advancements based on extracts of natural ingredients such as seaweed, raspberry, cactus or dandelion.
However, when placed under scientific scrutiny, the efficiency of herbal remedies seems to be limited to say the least and the scientific evidence supporting the advertising claims usually completely absent.
While side effects can, naturally, vary significantly depending on the exact content of the remedies, some of the most commonly reported side effects include bloatedness, flatulence, constipation and diarrhoea.
Illegal diet pills
Last, but not least, there is yet another group of weight loss medications, those which are unregulated and therefor illegal in the UK. All the relevant authorities and medical experts agree that these medications should be avoided at all costs not only because the results might be absent, but even more so because they can contain banned substances and thus have very dangerous side effects. Without license and scientific research, nothing can be sad about the efficiency or dangers of these medications.
If all this is not enough to highlight the clear and present danger illegal weight loss medications pose, than we should also mention that there have actually been numerous fatalities caused by illegal weight loss medications, most notably dinitrophenol.
Just some of the side effects of these medications include:
- Heart attack
- Kidney failure
- Psychotic episodes
- Accelerate heartbeat
How to lose weight safely and without risks?
If you are looking to lose weight, you should definitely make the right choice and act responsibly – by first contacting your doctor and consulting with him or her on your options. Once the doctor is familiar with your medical profile and history, then he will be able to suggest the best course of action.
For some, just lifestyle changes will be enough to make a difference, while others will require prescription medication to complement those efforts. In either case, talking to a doctor is the only way to ensure your safety.