XLS Medical Max Strength

Updated May 14, 2019.
Published Dec 21, 2016.
Dr. Krystal Crawford, ND, MS
Medically reviewed by Dr. Krystal Crawford, ND, MS, written by Jane Weston.

XLS Medical Max Strength is manufactured by Omega Pharma, and is part of the extensive XLS medical range. The supplement is incredibly overpriced, with a month’s supply costing anywhere between £44 and £65 for UK customers, or around $65 for international customers. The ingredients list does not explain what the mystery ingredient, Clavitanol, is. Also, the clinical trial that studied Clavitanol is not published publicly, which is not only unusual, but also frustrating!

We uncover the truth about XLS Medical Max Strength, including the ingredients, side effects, and what kind of results you should expect.


  • May help weight loss if you follow the plan and use as directed
  • Safe – some side effects, but nothing dangerous
  • Available everywhere – easy to buy


  • One of the most expensive weight loss supplements
  • Lack of transparency around clinical testing. What is Clavitanol?
  • Poor money-back guarantee
XLS Medical Max Strength Bottle
XLS Medical’s range of weight loss supplements has grown into quite a long list over the past few years, with one of the additions to the range being XLS Medical Max Strength. According to the advertising, it is 33% more effective than XLS Medical, the company’s first and original product; it supposedly blocks the digestion of fat, sugar, and carbohydrates.

Can this supplement help the consumer with healthy and effective weight loss? Below we take an in-depth look at XLS Medical Max Strength.

XLS Medical Max Strength Overview

What you need to know about XLS Medical Max Strength

We have mixed feelings about XLS Medical Max Strength.

The product is a certified medical device, which means that it should not interact with the body in any permanent way, and instead only acts upon the food eaten, allowing it to pass through the body undigested. This should be a guarantee of its safety; generally, it appears that there are no side effects that will have a significant impact upon the consumer’s health, but mild digestive side effects are seemingly common.

What are the side effects of XLS Medical Max Strength?

The customer reviews are incredibly mixed, and the product has seemingly a 50/50 chance of either aiding weight loss or causing side effects. It also seems that customers are likely to eat more while using XLS Medical supplements (not just this particular one), as they hugely overestimate the impact of the supplement; this can lead to weight gain!

How much does XLS Medical Max Strength cost?

The supplement is incredibly overpriced, with a month’s supply costing anywhere between £44 and £65 for UK customers, or around $65 for international customers.

Also, the clinical trial that studied Clavitanol is not published publicly, which is not only unusual, but also frustrating! We are only allowed to see the results that the company chooses to tell us, and we would have preferred to see more transparency around this and a full ingredients list that explained the mystery ingredient, Clavitanol. We are still none the wiser about what this is.

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XLS Medical Max Strength Key Features

XLS Medical Max Strength is one of a number of weight loss supplements offered by Omega Pharma. While other products in the XLS Medical range block of the proper digestion of either fat or carbohydrates in the stomach, XLS Medical Max Strength supposedly blocks the digestion of both carbohydrates and fats, by interacting and blocking some of the digestive enzymes that break down fat and carbohydrates.

One problem we have found with all XLS Medical products is that some consumers end up eating more, as they are under the mistaken belief that XLS Medical will prevent the absorption of the additional calories; this means that often people lose no weight or even gain weight while using the supplement.

XLS Medical Max Strength Key Points

  • Each bottle contains 120 tablets (1 month’s supply) and costs £63.74 in the UK
  • XLS Medical Max is made by InQpharm, a major European company
  • Works as a fat and carb blocker combined

XLS Medical Max Strength is manufactured by Omega Pharma, and is part of the extensive XLS medical range.

While the product cannot be purchased from the official website, customers can contact the XLS Medical team with any queries they have about the product or their diet.

The official website contains lots of information about the best way to combine XLS Medical products with a balanced diet. There is also an XLS Medical app, which provides the consumer with free access to their 12-week plan, a food diary, and “gentle reminders” to aid their weight loss journey. Some of this information also appears to be included in a leaflet that comes with the supplement.

How to Take XLS Medical Max Strength

You are recommended to take two XLS-Medical tablets with liquid up to 30 minutes before your two main meals of the day.

Do not exceed more than four tablets a day.

Drink plenty of water throughout the day, as this will aid in digestion and keep you hydrated.

You can also safely continue using XLS-Medical after you have reached your target weight, for example before consuming a particularly calorie-rich meal, to help maintain your weight or to prevent excess weight gain.

The manufacturers of XLS Medical Max Strength have described the product as follows:

XLS-Medical Max Strength reduces calorie intake from the main nutrients: carbohydrates, sugar, and fat. It contains Clavitanol™, a patented natural complex which reduces the breakdown and absorption of these nutrients into calories. This results in reduced calorie intake which helps you to lose more weight than dieting and exercise alone. It´s clinically proven.In addition, the reduced absorption of dietary carbohydrates helps lower blood glucose and insulin levels, which helps in reducing food cravings and blood glucose management.

They add that:

XLS-Medical Max Strength is a certified medical device for effective weight management, when taken in combination with a balanced diet and regular physical activity. It has a well-established safety profile and tolerability.

XLS Medical Max Strength Concerns

  • Is using a supplement to block fats and carbs after you have eaten them, a good habit for long-term weight loss?
  • Could be an expensive waste of money if it does not work for you
  • The huge marketing campaign, a major company, it all looks very convincing. But is the supplement worth the price tag?

What does XLS Medical Max Strength claim to do?

“The active ingredient Clavitanol™ blocks some of the activity of various digestive enzymes. As a result some dietary carbohydrates, sugar and fat are left undigested as they are too large to be absorbed in the intestine, helping you lose weight fast as they are naturally passed through your system.”

Does XLS Medical Max Strength work?

When trying to establish whether a product will work, we look at the ingredients used, the quantities that they are used in, and also turn to customer reviews, to see how the product works in practice.

The product contains just one active ingredient; the manufacturers of the supplement and the patented active ingredient do not explain what this ingredient is beyond its name, Clavitanol. They do however quote an unpublished study that they funded, which appears to show that the product does increase the consumer’s rate of weight loss. The study used a very high-carb, low-protein diet, which may have factored heavily into the results.

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XLS Medical Max Strength Ingredients

There is only one ingredient found in XLS Medical Max Strength, which is Clavitanol.

This ingredient is also known by the less-than-catchy name of IPQ-VV-102, but there is no actual information available to explain what Clavitanol is made from. It is also difficult to find information about the quantities used in this supplement, or how many capsules are supposed to be taken per day, or per dose.

We believe that consumers are instructed to take four capsules per day, split over two doses, before meals.

  • Clavitanol: According to the product information, clinical studies have been carried out to prove the efficacy and safety of Clavitanol. This substance has undergone a randomized, double-blind, placebo-controlled clinical study that took place in 2013 with 108 volunteers who were classified as overweight or obese. Each volunteer agreed to complete the study in the comfort of their homes and they were instructed to maintain a diet plan which was nutritionally balanced and mildly hypocaloric, with 55% of the energy from carbohydrates (a mixture of complex and simple sugars), 30% from fat and 15% from protein. The volunteers were split into two groups. One group received a daily dose of Clavitanol™, the active ingredient of XLS-Medical Max Strength, while the other group received a placebo. The volunteers did not know which group they were in but they all took 2 tablets with liquid immediately before two main meals of the day for a period of 12 weeks. After 12 weeks, the results clearly showed on average the group who had been taking Clavitanol™ lost 4x more weight than the dieters in the placebo group. The Clavitanol website states that the placebo group lost an average of 0.83 kg by the end of the 12 week period, while the Clavitanol group lost an average of 3.29 kg. The clinical research was carried out and funded by InQpharm group, the manufacturers of the ingredient.

XLS Medical Max Strength Side Effects

The manufacturers and sellers of XLS Medical Max Strength and Clavitanol are very keen for their potential customers to know that this supplement is well tolerated, with few or no side effects. However, as we read through the hundreds of negative reviews for this product, it became clear that some mild side effects are fairly common.

Customers could experience some of the following side effects:

  • Bloating
  • Constipation
  • Loose bowels or even diarrhea
  • Flatulence
  • Stomach cramps/Abdominal pain
  • Increased bowel movements

XLS Medical Max Strength blocks some digestive enzymes in the stomach (alpha-amylase, alpha-glucosidase, and lipase), which should prevent the digestion of some food, therefore reducing the calorific value of the consumer’s food slightly. However, it could also reduce the absorption of fat-soluble vitamins, and in the long term, deficiency is a possibility. It is also possible that this could affect the levels of these digestive enzymes in the stomach, which could lead to digestive problems (if used over a long period of time).

Caution: Not suitable for anyone under the age of 18. Not suitable for pregnant or breastfeeding women. Consult your doctor if you are unsure about the suitability of this or any other supplement.

XLS Medical Max Strength Customer Feedback

XLS Medical Max Strength has been reviewed hundreds of times on but the opinions and ratings of customers are hugely split – out of 483 reviews, 159 are one star rated, and 140 are five-star rated, with the rest of the reviews split between 2, 3 and 4 stars fairly evenly. Here are a few of the negative reviews:

Not for me – felt totally bloated all the time, followed to a tee and lost nothing apart from my money – you live and learn!

Not recommended at all infact didn’t make a difference in my weight loss at all I lost the same as the month before with the same exercise and healthy food involved pretty much threw my money with these

Absolute rubbish didn’t lose any weight was crampy,bloated and constipated. Husband lost a stone without them in the month.

I have been taking these tablets for 3 months and have lost 27lb BUT recently I was woken in the night with terrible stomach cramps which were uncontrollable. After 2 hours I couldn’t stand anymore and a visit to A and E and large dose of morphine later it was decided that it was XLS causing the pain. Needless to say I won’t be taking anymore!!!!!

The negative customer reviews are split between consumers who saw no differences when taking the supplement, and those who experienced unpleasant digestive side effects. Below we have selected a few of the positive reviews, as the product does appear to work for some consumers.

Definitely works if you don’t fall into psychological trap of eating more because it won’t matter with the pills. Have to diet at the same time.

I have been taking these tablets for 8 weeks now in conjunction with healthy eating and exercise. I have lost exactly 2 stone in this time and feel that these tablets have contributed massively to this. Alongside the increased weight loss I have definitely felt less hungry than when I’ve dieted in the past.

I find these work well, both as an acceleration to weight loss and as an appetite suppressant. I agree they need to be part of a calorie controlled diet, but the weight loss is quite a bit faster with them than without. I suspect this is not true for everyone, but it has been noticeably true for me.

XLS Medical Max Strength Money-Back Guarantee

XLS Medical Max Strength does not come with a guarantee. Returns policies will vary between each third party retailer that sells the product.

We believe that it is incredibly important that manufacturers offer a money back guarantee; it shows confidence in their product and its effectiveness, and helps to protect the customer’s wallet should they experience unpleasant side effects while using a supplement. Considering that XLS Medical Max Strength is a “certified medical device for effective weight management” which is “clinically proven” to work, we are very surprised that there is no money-back guarantee on this product.

Where To Buy XLS Medical Max Strength

XLS Medical Max Strength is available primarily in the UK. International customers can buy it on Amazon, but delivery estimates are anywhere between three and five weeks!

On Amazon’s UK website, a packet of 40 tablets (a 10-day supply) costs £19.00 plus delivery charges (or free delivery if the customer has a Prime subscription). A packet of 120 tablets (1 month supply) costs £44.28 with free delivery.

On Amazon’s international website, a packet of 120 tablets costs $64.49, with free shipping. There is also a two-pack offer, which costs $129.85 with free shipping.

One bottle of 120 tablets (1 month’s supply) costs £63.74 when bought from It is also available in selected Boots stores across the UK. A three month supply (360 tablets) costs £154.99 at Shipping charges may also apply.

XLS-Medical Max Strength is a very expensive supplement, especially because consumers appear to need to take a large number of pills per dose. While offers a significant discount compared to Boots; it is still a very expensive weight loss supplement!

Watchdog Verdict

Overall, we dislike that the manufacturers are happy to make huge claims about the product’s potency, but will not fully publish the study that supposedly proves these claims, or provide any detailed information about what Clavitanol is.

The product is incredibly expensive, which could be justified if the product was incredibly effective. Unfortunately, the reviews suggest that at least 50% of consumers fail to lose significant amounts of weight with the supplement, or experience such unpleasant side effects that they are unable to use the supplement.

Overall, we do not recommend XLS Medical Max Strength to our readers.

XLS Medical Max Strength Frequently Asked Questions (FAQ)

What is XLS Medical Max Strength?

XLS Medical Max Strength is a weight loss supplement supposed to stop the digestion of fat and carbohydrates.

What are the side effects of XLS Medical Max Strength?

Users can experience unpleasant side effects such as bloating, constipation, diarrhea, flatulence, stomach cramps, and abdominal pain.

What are the ingredients in XLS Medical Max Strength?

XLS Medical Max Strength contains a single ingredient known as Clavitanol. Clavitanol is, in fact, a proprietary patented complex made of microcrystalline cellulose, hydroxypropyl methylcellulose, tri-calcium phosphate, and magnesium stearate.

Does XLS Medical Max Strength work?

There is a lack of scientific evidence to prove the effectiveness of XLS Medical Max Strength.

How much does XLS Medical Max Strength cost?

Depending on where you buy, a month’s supply can cost between £44.00 and £65.00.

Who makes XLS Medical Max Strength?

XLS Medical is owned by Omega Pharma, a British company based in London.

How do I take XLS Medical Max Strength?

Take two tablets 30 minutes before your two main meals of the day. Do not exceed four tablets a day.

Can I take XLS Medical Max Strength if I have a health condition?

It is better to consult your doctor before taking this supplement. You should avoid it if you are pregnant or breastfeeding.

Does XLS Medical Max Strength have a money-back guarantee?

There is no money-back guarantee offered for XLS Medical Max Strength.

How long has XLS Medical Max Strength been around?

XLS Medical Max Strength is the latest addition to the XLS Medical family and has only been on the market for a couple of years.

Where can I buy XLS Medical Max Strength?

XLS Medical Max Strength is available online from Amazon or at different retail stores such as Tesco, Asda, and Boots. You can also find it at Holland & Barrett.

Can I buy XLS Medical Max Strength in stores?

Yes, it is sold at Tesco, Asda, Boots and many more.

How do I contact XLS Medical Max Strength customer service?

You can contact XLS Medical by email via a contact form available on their website.

Are there any XLS Medical Max Strength coupons?

There are no XLS Medical Max Strength coupons available at this time.

Are there any free samples of XLS Medical Max Strength?

XLS Medical does not offer free samples of their products. Since there is no money-back guarantee, we recommend caution.

How does XLS Medical Max Strength compare to Phentaslim?

Criteria XLS Medical Max Strength Comparison Phentaslim comparison
Clinically Proven Ingredients
Side Effect Free
Positive Customer Reviews
24/7 Support
Money-back Guarantee

Disclaimer: Our reviews and investigations are based on extensive research from the information publicly available to us and consumers at the time of first publishing the post. Information is based on our personal opinion and whilst we endeavour to ensure information is up-to-date, manufacturers do from time to time change their products and future research may disagree with our findings. If you feel any of the information is inaccurate, please contact us and we will review the information provided.

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