Weight Loss Tablets

What are weight loss pills?

Weight loss pills are medicines that can support weight loss as part of a wider plan that includes changes to your diet and lifestyle. They come as tablets or capsules and are designed to make weight loss easier, not to replace healthy habits altogether.

Weight loss pills include:

• orlistat 120mg
• Xenical (orlistat 120mg)
• Mysimba (naltrexone and bupropion)
• Alli (orlistat 60mg)
• Orlos (orlistat 60mg)

There's an important difference between licensed medication and supplements. Licensed weight loss medicines have been clinically tested, are regulated by the MHRA, and have proven evidence behind them.

Weight loss supplements sold in health shops or online are not held to the same standards and may not have reliable evidence to support their claims.

When people talk about weight loss pills that ‘actually work’, they're generally referring to licensed medicines rather than supplements.

Do weight loss pills actually work?

Yes, clinically approved weight loss pills can help you lose weight. However, results vary from person to person. Factors like your starting weight, your diet, how active you are, and how consistently you take them all make a difference.

Weight loss pills work best when combined with a reduced-calorie diet and regular physical activity. Remember, they're a tool to support your efforts, not a standalone solution.

Weight loss pills available in the UK

Prescription weight loss pills

Orlistat 120mg and Xenical

Orlistat 120mg is the generic, unbranded version of Xenical, which is the branded version of the same medicine. Both are equally effective, though orlistat is often available at a lower cost.

They're typically recommended for people with a body mass index (BMI) of 30 or above, or 28 or above, alongside a weight-related health condition like type 2 diabetes or high blood pressure.

Orlistat works by blocking fat. When you eat a meal, it prevents your digestive system from breaking down around a third of the fat in your food. That undigested fat can't be absorbed by your body and is passed out of your system when you go to the bathroom.

When paired with a low-fat diet and regular exercise, you could lose 5% of your body weight over three months.

Both are only available on prescription. To see if orlistat 120mg or Xenical is suitable for you, complete a short consultation with us by answering some health, medical, and lifestyle questions.

Our expert clinicians will review your answers and, if it's right for you, we'll deliver it quickly and discreetly to your door.

Mysimba

Mysimba is a prescription-only tablet that contains two active ingredients, naltrexone and bupropion.

Rather than blocking fat, Mysimba works by targeting the areas of the brain involved in appetite and reward, making it easier to eat less and resist food cravings. When used alongside a calorie-controlled diet and regular exercise, it can help support meaningful weight loss over time.

When taking Mysimba, you could lose up to 5% of your body weight by week 16, and a further 8% by week 56.

It's typically recommended for people with a BMI of 30 or above, or 27 or above alongside a weight-related health condition.

Mysimba is only available on prescription and isn't suitable for everyone. To see if Mysimba is right for you, complete a short consultation with us.

Over-the-counter weight loss pills

Alli and Orlos (orlistat 60mg)

Alli and Orlos both contain orlistat at a lower dose of 60mg and are available to buy over-the-counter without a prescription.

They contain the same active ingredient and work in exactly the same way, so the choice between them often comes down to personal preference. Both are typically recommended for people with a BMI of 28 or above.

When you eat a meal, they prevent your digestive system from breaking down some of the fat in your food. They also need to be combined with a low-fat, calorie-controlled diet and regular exercise.

Results are more modest than with prescription-strength orlistat, but they can be a helpful starting point, particularly if your BMI is slightly below 30 and you feel you'd still benefit from losing some weight for your health.

For example, for every 2lb you lose, they can help you lose an extra 1lb.

Are there semaglutide tablets for weight loss?

Semaglutide is best known in the UK as Wegovy (for weight management) and Ozempic (for type 2 diabetes), both of which are injections. Semaglutide tablets do exist under the name Rybelsus, but they're licensed for type 2 diabetes rather than weight loss specifically.

However, in certain cases, Rybelsus can be prescribed off-label for weight loss, which simply means using a medicine for a different condition than it was originally licensed for. This is common, legal, and safe when done under proper medical supervision.

A weight loss tablet may also become available in the future, which could be particularly beneficial for those who prefer not to use injections. Though we can’t confirm this at the time of writing.

Do GLP-1 weight loss pills work better than other weight loss tablets?

The only GLP-1 pill available at the moment is Rybelsus, which can sometimes be prescribed off-label for weight loss, following a clinical assessment. GLP-1 medicines work by reducing appetite and helping patients feel fuller for longer, unlike weight-loss tablets like orlistat, which work by reducing fat absorption from food.

Studies show that GLP-1 medicines, like semaglutide, generally produce more weight loss than capsules like orlistat. But this can vary between person to person.

How weight loss pills work

Different weight loss pills work in different ways.

Orlistat, Xenical, Alli, and Orlos all work by reducing the amount of fat your body absorbs from food. When you eat fat, orlistat prevents some of it from being broken down and absorbed, so it passes through your body instead.

Mysimba works by targeting the areas of the brain involved in appetite and reward. It helps reduce hunger and makes it easier to resist food cravings, which can support you in eating less over time.

Neither type is a magic fix, but understanding how they work can help you make an informed choice and get the most out of your treatment.

Are weight loss pills safe?

Licensed weight loss pills are regulated by the MHRA, which means they've been through rigorous testing for safety and effectiveness before being approved for use in the UK.

Like all medicines, they can cause side effects, and they're not suitable for everyone.

A pharmacist can review your medical history, check for any reasons the medicine might not be right for you, and give you clear guidance on how to take it safely.

Buying from a regulated pharmacy (like us) is the best way to make sure you're getting a genuine, licensed medicine with the right support behind it.

Are weight loss pills available on the NHS?

Availability on the NHS depends on the medication. Orlistat 120mg and Xenical can be prescribed on the NHS by your GP if you have a BMI of 30 or above, or 28 or above with a weight-related condition.

Alli and Orlos (both 60mg orlistat) are available over-the-counter without a prescription. Mysimba is no longer available on the NHS and can only be obtained privately.

Who should consider weight loss pills

Weight loss pills may be a suitable option if you:

• have a BMI above 30 or 28, or 27 and above, alongside a weight-related health condition
• have already made efforts to lose weight through diet and exercise, but have struggled to achieve meaningful or lasting results
• prefer a tablet over injections

If you're unsure whether they're suitable for you, our pharmacists are here to help.

What is the strongest weight loss pill available?

It's understandable to want to know which option will give you the best results, but effectiveness varies from person to person. There's no single pill that works the same way for everyone, and what is most effective for one person may not be the right choice for another.

In the UK, prescription-strength options like orlistat 120mg, Xenical, and Mysimba tend to stronger than over-the-counter treatments like Alli or Orlos, which contain a lower dose of orlistat.

Injectable weight loss treatments, like Mounjaro or Wegovy, are also available and may be an option if pills aren't suitable or effective for you. Our expert clinicians can talk you through all the options and help you decide which treatment is most likely to work for your situation.

Side effects of weight loss pills

Like all medications, weight loss pills can cause side effects, but not everyone gets them. The side effects you may experience depend on which medication you take.

Most people experience side effects when they first start treatment or increase their dose. If you do experience side effects, they’re usually mild and improve as you change your diet and your body adjusts to treatment.

Orlistat works by reducing the amount of fat your body absorbs from food, so most side effects are digestive and linked to fat intake. That’s why it’s so important to eat lower-fat meals to reduce the likelihood of these side effects.

Common side effects can include:

• oily or greasy stools
• an oily discharge from your anus (you may have oily spots on your underwear)
• a sudden urgency to use the toilet
• diarrhoea
• bloating and wind
• stomach pain
• headaches

Common Mysimba side effects may include:

• nausea or vomiting
• constipation
• headaches
• anxiety or irritability
• dizziness or vertigo
• feeling shaky (tremor) or jittery
• difficulty sleeping (insomnia)
• changes in the taste of food, or dry mouth
• difficulty concentrating
• tiredness, drowsiness, or lack of energy
• ringing in the ears (tinnitus)
• fast or irregular heartbeat
• hot flushes
• increased blood pressure (sometimes severe)
• stomach pain or pain in the upper abdomen
• excessive sweating
• rash or itching
• hair loss

Always read the patient information leaflet before use and follow your prescriber's advice. If any side effect is severe, persistent, or worrying you, speak to your prescriber or GP for advice.

Alternatives to weight loss pills

Pills aren’t the only option when it comes to weight loss treatments. Depending on your health, preferences, and goals, you might also want to consider weight loss injections or lifestyle programmes.

Weight loss injections are typically administered once a week and work by reducing your appetite, leaving you feeling fuller for longer. They also help reduce food noise and cravings, so you naturally eat less and, over time, lose weight.

Mounjaro is clinically proven to help you lose an average of 22.5% of your body weight, making it one of the most effective weight loss treatments currently available.

Wegovy is clinically proven to help you lose an average of 21% of your body weight and is available at a lower price point than Mounjaro.

Lifestyle programmes can be effective, particularly when used alongside medication. Remember, our pharmacists can provide regular check-ins, help you track your progress, and adjust your treatment plan if needed.

Buying weight loss pills safely online

Buying weight loss medication online can be safe and convenient, but only when you use a registered and regulated pharmacy. There are, unfortunately, a number of unregulated websites selling counterfeit or unlicensed products that could be ineffective or even harmful.

To stay safe, always make sure you:

• Buy from a pharmacy registered with the General Pharmaceutical Council (GPhC). You can verify this on the GPhC website.
• Complete a proper medical consultation before purchasing prescription medication. This may be an online questionnaire or a consultation with a pharmacist, but it's a legal and clinical requirement.
• Avoid any website that offers prescription medication without any form of health check, or that makes unrealistic promises about results.

Chemist4U is a fully registered and regulated UK pharmacy. All prescription weight loss treatments are dispensed only after a clinical consultation to make sure they are safe and appropriate for you.

Frequently asked questions about weight loss pills

What weight loss pills actually work in the UK?

Orlistat (Xenical, Alli, Orlos) and Mysimba are the licensed options in the UK. Both are clinically proven to support weight loss when combined with a healthier diet and lifestyle.

What is the best weight loss pill available?

It depends on the person. Prescription-strength options like orlistat 120mg, Xenical, and Mysimba tend to be more effective than over-the-counter treatments. Our clinicians can help you find the right weight loss treatment for you.

How much weight can you lose with weight loss pills?

Results vary, but people taking orlistat alongside a calorie-controlled diet can typically expect to lose around 5% of their body weight over 3-12 months. Mysimba has shown similar results.

How quickly do weight loss pills work?

Both orlistat and Mysimba can start to have an effect within a few weeks, but noticeable weight loss typically takes longer. Results build gradually over months, which is why consistency with both your medication and your lifestyle (diet and exercise) is so important.

Can you buy weight loss pills online safely?

Yes, as long as you use a GPhC-registered pharmacy that requires a proper consultation. Avoid any site that sells prescription medication without a health assessment.

Who should not take weight loss pills?

Weight loss pills are not suitable for everyone, including those who are pregnant, breastfeeding, or under 18. For more information, refer to the patient information leaflet for your specific medication.

Are weight loss pills better than injections?

While weight loss injections have shown stronger average results, pills suit some people better. Everyone is different, and what is better for one person may not be right for another.

Do weight loss pills work without dieting?

Weight loss pills work best alongside a healthy, balanced diet. With orlistat, continuing to eat a high-fat diet is likely to cause side effects and will make your treatment less effective.

Building healthy habits during treatment also matters for the long term, as they are what will help you maintain your weight loss once you come off medication.

Are there prescription weight loss pills in the UK?

Yes. Orlistat 120mg, Xenical, and Mysimba are all prescription-only weight loss pills.

Are weight loss pills suitable for long-term use?

With orlistat, treatment should only continue beyond three months if you have lost at least 5% of your body weight. Mysimba should be stopped after 16 weeks if 5% weight loss has not been achieved.

Once you have reached your target weight, speak to your prescriber about stopping treatment. If you have not lost weight after three months on either medication, again, speak to your prescriber for advice.

Do pharmacists prescribe weight loss pills?

Yes. Our prescribing pharmacists have an additional qualification which enables them to prescribe prescription-strength treatments, like weight loss pills.

Sources

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