Orlistat vs Wegovy

Orlistat is one of the oldest weight-loss treatments of its kind, whereas Wegovy, specifically the Wegovy pill, is one of the newest. Two weight-loss tablets released over 20 years apart - how do they stack up against each other? How does the original form of Wegovy, the Wegovy injection, compare to both?

This article will take you through all the aspects and differences between Orlistat and both forms of Wegovy for a complete overview. We'll compare the three treatments in detail, covering side effects, administration, and effectiveness rates, so you have the information you need before committing to a weight loss treatment plan with Prescription Doctor.

START YOUR CONSULTATION TODAY

Is Orlistat the Same As Wegovy?

Orlistat and Wegovy aren't the same treatment, but both can support your weight loss journey in very different ways. Orlistat is available as Xenical, Alli, or generic Orlistat, while Wegovy can be taken as a daily pill and a weekly injection. The different names of Orlistat don't change the medication much; the only notable difference among the three is that Alli has half the potency of the other two.

By comparison, the two forms of Wegovy have very different ingredient lists; because they are administered differently, they must be formulated differently, too. They both still contain the same active ingredient: semaglutide. To maximise weight loss on either treatment, pair it with a healthy diet and regular exercise. Dietary changes are especially important for Orlistat, as that is the main feature of the treatment.

Orlistat vs Wegovy at a Glance

The table below summarises the rest of the article into a condensed, easy-to-compare format. We advise you to continue reading to gain a deeper understanding of all aspects of the treatments, but if you prefer knowing the stats at a glance, here they are:

How Do Orlistat and Wegovy Work?

The treatments take effect via their respective active ingredients; for Orlistat, the active ingredient is orlistat, while Wegovy’s is semaglutide. First, let’s look at Orlistat.

Orlistat reduces fat in meals by up to 33%. It works in the digestive system and blocks lipase enzymes, which are responsible for fat absorption. Reducing your fat intake also reduces your calorie intake, which is how it boosts weight loss rates when combined with other healthy lifestyle practices.

Wegovy has two effects in the body: one in the digestive system, like Orlistat, and one in the brain. When you eat food on Wegovy, it slows digestion. This doesn’t mean you don’t get the nutrients you need, just that it takes longer to absorb them. This slowing keeps you feeling fuller longer, reducing how much food you consume overall.

The secondary effect of Wegovy is that it changes how your brain perceives appetite. By interacting directly with the brain, Wegovy can alter how quickly it signals hunger. This makes you feel mentally fuller, while your stomach feels physically fuller too. This fullness is what makes Wegovy so effective; you will feel less desire to overeat and snack between meals while on treatment.

Orlistat vs Wegovy Weight Loss Results

Of the three treatments, Wegovy injections lead in weight-loss rates. In clinical trials, it averaged an 18.7% total body weight reduction at its highest dosage, 7.2mg. Next is the Wegovy pill, which averages 13.6% weight reduction at the highest dosage of 25mg. Lastly, Orlistat offers 5.9% weight loss; this treatment has no dosage increases, as Orlistat and Xenical both contain 120mg.

How to Take Orlistat and Wegovy

Orlistat is the simplest of the three medications; swallow the pill whole with water. Take it immediately before a meal, during, or up to an hour after.

Wegovy pills are substantially more complex, as they do have certain fasting periods. You take one Wegovy pill once a day, on a completely empty stomach. To do this, you must fast for 8 hours before taking it, then fast a further 30 minutes after you swallow it. You must swallow it with no more than 120ml of plain water, and you cannot ingest anything else at that time. This includes food, drinks, and other oral medications.

Wegovy injections are administered weekly and have no food-related administration requirements. You can inject them yourself, or with the aid of another, and there are three injection sites you can choose from, as illustrated below.

If you wish to inject your arm, it is advised to do so with the assistance of another person, as it can be a hard spot to reach solo. You should rotate your injection spot each week - not the site as a whole, but alternating between your left and right thighs or left and right sides of your stomach would be best.

Orlistat and Wegovy Dosage Information

Follow the dosage schedule for each treatment to get the most out of the medication and stay safe. Orlistat has the most flexible dosage schedule, so we will start there first.

Orlistat pills are to be taken immediately before meals or up to an hour after, or during if you wish. You can take them once, twice, or three times a day, depending on what you eat. Your clinician can advise you on how many to take depending on your meals, but the choice is yours. You can omit your post-meal dose if the meal contains no fat. No fat means Orlistat won’t have anything to do in the body!

Next, let’s look at Wegovy pills. Take these daily, but don't miss doses or take more than one a day. If you do miss a dose, skip that day’s dose and resume the normal schedule the following day. To increase your Wegovy pill dose, you do not take multiple pills, but you ‘titrate’ instead. This means that (with a clinician's approval) your dose strength will increase while remaining at one pill per day. The titration schedule is illustrated below:

Wegovy injections also follow a titration schedule. You administer injections once a week, unlike the two pills. The dosage schedule is similar to the Wegovy pill, usually increasing every 4 weeks until you reach the highest dose, which you will stay at for the rest of treatment if needed. The schedule is below:

Side Effects of Wegovy and Orlistat

All medications have the potential to cause unwanted side effects, and for many, they can be one of the deciding factors when choosing a treatment. Here are the side effects of Orlistat, Wegovy injections, and Wegovy pills:
 

Further side effects are listed for all four treatments. These include effects occurring in 1 in 100 cases and those for which the frequency cannot be estimated from the available data. They can all be found in the Patient Information Leaflets for Alli, Xenical, Wegovy injections and Wegovy pills.

Can You Take Wegovy and Orlistat Together?

No, you should not take Wegovy and Orlistat at the same time, as this could increase the frequency and severity of side effects. The results of doubling up on weight-loss treatments are largely unknown, so for your safety, you should not do this.

Orlistat or Wegovy: Which is Better?

Many factors matter when choosing a weight-loss treatment, and in many cases no option is strictly ‘better’. If you're going purely off weight-loss rates, Wegovy injections come out on top, at an impressive 18.7%. Next come Wegovy pills at a healthy 13.6%, then Orlistat at 5.9%.

Cost, availability, and administration should also be major factors. If you have a dislike of needles or frequently travel, one of the pills would be better suited to you. If you think fasting may be difficult, Orlistat or Wegovy injections could be a better fit. If you are ever unsure or want to weigh your options, our clinicians are here to help.

Can I Switch Between Wegovy and Orlistat?

Switching from Wegovy to Orlistat, or vice versa, is possible under clinician supervision. They will determine if swapping is your best option, how well your body may react to the swap, and which dosage you will start at (if switching to Wegovy). Swapping between forms of Wegovy (i.e., pen to pill or pill to pen) is also possible under these conditions.

Are There Any Alternatives?

Plenty of alternatives exist to both Orlistat and Wegovy, and you may prefer a different treatment for any reason. It could come down to cost, availability, ingredients - simply get in touch with one of our clinicians, and they will help you review your options. Prescription Doctor offers a range of options, including Mounjaro, Foundayo, Mysimba, and more.

Healthy Practices with Prescription Doctor

Orlistat, Wegovy injections, Wegovy pills - whatever you choose, we’ll be there for you. We’ve been helping people with their weight-loss journeys since 2013, so we know our stuff. We provide personalised support to everyone who needs it through our dedicated, professional service, helping your treatment run as smoothly as possible.

If you choose to start any of the treatments mentioned in this article, you can start your consultation by filling out a short online form, with no in-person consultations or awkward phone calls required. From there, our clinicians will review your information to determine the right option for you.

If you want more information about any of the treatments, we have articles that cover the topics mentioned in more detail, such as side effects, dietary advice, and administration. If you’re ready to start your consultation, get in touch today, and we’ll help however we can.

Authored & Reviewed By

Mohamed Imran Lakhi

MPharm - Lead Pharmacist

Imran Lakhi is the superintendent pharmacist and founder at Prescription Doctor. He has been at the core of our team.

Published on: 30/10/2026 Reviewed on: 30/10/2026