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How quickly do you lose weight on Zepbound?

Robbie Puddick
Written by

Robbie Puddick

Medically reviewed by

Fiona Moncrieff

4 min read
Last updated June 2024

Jump to: How effective is Zepbound for weight loss? | Is Zepbound available in the UK? | Is Zepbound available on the NHS? | How much does Zepbound cost in the UK? | Which is better, Wegovy or Zepbound? | Does Zepbound have side effects?

According to randomised controlled trials, you start losing weight immediately after taking Zepbound. After four weeks, the average weight loss is around 2% of body weight; after eight weeks, it’s over 4%.

Zepbound (tirzepatide) reduces appetite and hunger, helping you eat fewer calories; this effect is almost immediate.

However, you might notice the impact of lower hunger wearing off after 4-5 days post-injection in the first month of taking Zepbound.

It can take around four weeks for Zepbound to reach a level in the body we call a steady state. A steady state is when the drug’s levels in the body remain consistent rather than spiking and falling.

Interestingly, this initial weight loss is no different to other weight loss treatments or the impact of diet interventions on weight loss. The real effect of tirzepatide is seen beyond three months.

Tirzepatide is a long-acting medication that’s started at a lower dose to reduce the number and severity of side effects as it’s built up to a higher maintenance dose.

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How effective is Zepbound for weight loss?

Research suggests that Zepbound leads to an average weight loss of around 25% after one year. If you weighed 100 kg, that would be a weight loss of 25kg.

This research also showed the percentage of participants on Zepbound achieving more than 10% weight loss is incredibly high. 92% of participants on Zepbound achieved more than 10% weight loss, with 84% achieving more than 15%.

Achieving over 10% weight loss is associated with clinically significant reductions in risk of chronic conditions such as type 2 diabetes and heart disease.

Is Zepbound available in the UK?

Zepbound has been approved for weight loss and type 2 diabetes in the UK under the brand name Mounjaro and is available with Second Nature.

We launched our Mounjaro weight-loss programme which includes access to a registered dietitian or nutritionist to help you to develop the healthy habits you need to keep the weight off for good.

However, you must meet strict eligibility criteria and complete an initial consultation with our clinical team.

Is Zepbound available on the NHS?

You can’t get Zepbound on the NHS yet, and it’s unclear when it will be prescribed through the NHS.

It may only be available as a private prescription before becoming more widely available on the NHS through specialist weight management services.

How much does Zepbound cost in the UK?

If you’re prescribed Zepbound via the NHS, you’ll only need to pay the base fee of £9.95 for a prescription.

Via private prescription, buying Zepbound and the injectable pens required for four weeks would cost around £300 with Second Nature when it’s available.

In the UK, Zepbound is sold under the brand name Mounjaro.

Which is better, Wegovy or Zepbound?

The higher doses of Zepbound (10mg & 15mg) are more effective for weight loss and blood sugar than Wegovy, based on an indirect analysis of individual studies.

Zepbound supports an average weight loss of around 25% after one year, whereas on Wegovy, it’s around 16%.

However, no studies have compared the two medications directly against one another in a double-blinded randomised controlled trial (where neither the researchers nor the participants know which medication they’ve been given).

So, Zepbound seems more effective than Wegovy for weight loss, but we need a study comparing the two weight-loss injections to confirm this.

Does Zepbound have side effects?

The most common side effects of Zepbound are nausea, constipation, vomiting, and other symptoms affecting the gastrointestinal (GI) tract, like diarrhoea.

You might also experience less common side effects like tiredness or headaches.

These symptoms most commonly occur around the time of the injection, during dose escalation, and are typically transient and will ease after you’ve adapted to the medication.

However, everyone responds differently to these medications; some people won’t experience any side effects, while others will have to discontinue their medication due to the discomfort the side effects cause.

Not a magic pill

Weight-loss injections are designed as additional tools for healthy lifestyle change and shouldn’t be considered as lifelong medications.

Instead, they should be used to help you kickstart your weight-loss journey whilst you focus on building new, healthy habits.

Consider the use of antidepressants for people living with depression. They’re not designed to cure the condition. Instead, they’re designed to allow room for therapy to treat the condition’s underlying cause.

Mounjaro and Wegovy are similar. These medications can help silence food-related thoughts and also give you a boost of confidence with more immediate weight-loss results.

This helps to buy you the time and headspace to understand why your body may have struggled to lose weight previously, and to build new long-term healthy habits.

The core focus of our medication programmes are to calm down the feeling of food noise, lower your cravings, and to allow you to build healthier habits to keep the weight off for good.

The ultimate goal is to make losing weight feel second nature.

Second Nature’s medication-supported programmes

Second Nature has two medication-supported programmes: a Wegovy weight-loss programme and a Mounjaro weight-loss programme.

If you’ve made the decision to try Wegovy or Mounjaro (assuming you’re eligible), why should you choose Second Nature over other medication providers?

For peace of mind.

Second Nature has worked with the NHS for over 6 years providing weight-loss programmes across the UK.

Whilst our Wegovy and Mounjaro weight-loss programmes are private and not currently used by the NHS, we’ve built the programmes with a focus on scientific evidence, patient safety, and data security.

We hope that our 6+ years of working with the NHS and building a track record of effective weight-loss results will give you peace of mind to give us a try.

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