Weight loss pills may hold a world of promise, particularly for people who have tried in vain to find a diet which works for them. Yet slimming pills should be used to support a diet, rather than being relied on for weight loss.

Weight loss pills can be prescribed by your doctor to help combat obesity. Generally, drug’s prescribed by your doctor are more likely to be effective and safer than non-prescription tablets.

If you decide to purchase any slimming pills or herbal supplements , you should let your doctor know.

Who are diet pills suitable for?

Whilst diet pills vary in terms of how they work, the ones available from the NHS and chemists are those that work by blocking the full digestion of the energy from food. Fat binders prevent fat from fully being digested and carb blockers impair the digestion of carbohydrate.

These diet pills therefore may be suitable for people who find it difficult to adequately regulate their diet without the help of the pills. There are those of us who consistently struggle with choosing appropriate portion sizes and others who have psychological reasons for overeating, such as those prone to comfort eating. There may also be other reasons behind a need to consider weight loss pills.

Note that if you have type 2 diabetes, are obese and have struggled to lose weight, you may benefit from certain type 2 diabetes drugs that also facilitate weight loss such as incretin drugs , SGLT-2 inhibitors or alpha-glucosidase inhibitors

Are weight loss pills safe?

For prescribed drugs, research is carried out prior to a medication being approved for use.

Currently, only one weight loss pill, orlistat, is approved specifically for treating obesity on the NHS.

Note that any drug that is powerful enough to help you lose weight is also likely to include side effects that should be considered before taking the treatment. Side effects can range from unpleasant side effects, such as bowel discomfort or nausea, through to very serious side effects, depending on the treatment.

As an example, orlistat, despite being approved for use on the NHS, has been linked with rare cases of liver injury. The safety profile of diet pills that have not been approved is less likely to be known and therefore it is harder to know how much risk these other pills involve. It is advisable not to take risks with diet pills that have not been approved.

Where can I buy diet pills safely?

Orlistat – also known as Alli or Xenical

Orlistat, sold under the trade names Alli and Xenical, inhibits the digestive enzymes that break down fat which prevent it being absorbed by the body.

Approximately a third of the fat you eat will be blocked by orlistat. One orlistat capsule is taken with each meal that contains fat.

Orlistat has been found to be effective when used in conjunction with an appropriate diet , with those who took the pill having more success than those who didn’t. Taking orlistat can therefore help your diet to be more effective.

Orlistat is only prescribed in people with a BMI of at least 28 that have failed to lower their weight through lifestyle changes, such as diet changes and increased physical activity.

Side effects of orlistat include oily and smelly stools, flatulence and frequent needing to go to the toilet. The side effects are related to the fact that undigested fat is being passed out of your body diet, therefore if you lower the fat content of your diet, you will help to relieve the side effects.

The side effects are most prevalent when you first take the pills and tend to reduce over time.

Weight loss pills can be suspended

A number of effective weight loss pills have been suspended from being marketing by the Medicines and Healthcare products Regulatory Agency (MHRA).

Slimming pill sibutramine, marketed as Reductil, was suspended in February 2010 on account of it being linked with an increased risk of heart attacks and strokes

Rimonabant, marketed as Acomplia, was suspended from the marketed as a result of an increased likelihood of psychiatric disorders.

Fat binding pills

Fat binding pills such as Proactol and Lipobind and XLS-Medical Fat Binder, are based on dried cactus extract.

They claim to help to eliminate fat from meals by binding the fat with dietary fibre in the meal. The binded fat-fibre mass is not absorbed by the small intestine and passes out of the body. This means that a proportion of the calories in the fat you eat is not absorbed. The makers claim that unlike with orlistat there are no side effects.

As with orlistat, fat binding pills are likely to be more useful to those who need help with cutting fat content from their diet. As fat binders are yet to be approved for use on the NHS, the effectiveness, health risks and side effects are not as well known as for orlistat.

Carb blockers

Carb blockers, such as XLS-Medical Carb Blocker, work by inhibiting the action of the digestive enzyme alpha-amylase which allows some of the carbohydrate from meals to pass through and out of the gut undigested. This means that not all the calories in the carbohydrate you eat will be digested.

Carb blockers may be suitable for people that are struggling to cut down on the amount of carbohydrate they eat. It is advisable not to use carb blockers for prolonged periods of time. Note that the type 2 diabetes drugs Glucobay ( acarbose ) and Glyset (miglitol), which are known as alpha-glucosidase inhibitors drugs, are also carb blockers.

These drugs are available on prescription for people with type 2 diabetes if your doctor agrees that you would benefit from them.

Hoodia gordonii

Hoodia gordonii is a South African plant that has been used by bushmen as an appetite suppressant. The Hoodia plant is a protected plant species and harvesting rights have only been granted to a few companies. It’s thought that a number of supplements that claim to contain Hoodia may not.

Of the drugs which do, currently no clinical research is available to back up the claim that it can be used as an appetite suppressant.


Capsiplex is a product based on chilli and capsicum.

The drug claims to be able to speed up your metabolism. The drug saw a great deal of press hype following its introduction in June.

Chili is known to help improve your metabolic rate and as a result Capsiplex, being based on chilli, has similar effects.
As with all so-called fat burning pills, it helps to increase the weight loss results of an effective diet.

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