Zepbound (Tirzepatide) Injection

Zepbound is a weight loss treatment that contains tirzepatide, a prescription-only medication that can be used for 2 conditions: weight loss and type 2 diabetes. It comes in the form of an injectable pen, containing 4 doses you inject yourself once per week at around the same time.

Zepbound is only prescribed for weight loss and is the brand name for tirzepatide in the USA. It’s manufactured by the same company that makes Mounjaro, called Eli Lilly.

How does Zepbound work?

Zepbound’s active ingredient, tirzepatide, mimics 2 hormones that are usually released after eating, called glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP).

These are both a type of incretin hormone, working in 3 main ways:

1. Slowing down the rate at which you digest food to keep you feeling full for longer.
2. Signalling to your brain that you’re full, lowering appetite.
3. Regulating blood sugar by increasing insulin levels.

As tirzepatide mimics these hormones, the same receptors in your body are triggered, tricking your body into carrying out the same actions. When you take Zepbound (or Mounjaro) week after week, you should notice you feel less hungry, can eat less, and feel full after eating and between meals. If you also have conditions like prediabetes, it could help to improve your blood sugar levels and reduce cravings caused by spiking sugar levels.

Zepbound dosage schedule

Zepbound is prescribed at the lowest dose of tirzepatide: 2.5mg for 4 weeks. You’ll then increase the dosage every 4 weeks, although you can choose to stay on a lower dose for longer if you need more time to get used to the treatment, or if it’s working well for you at a lower dose.

As Mounjaro is the UK version of Zepbound, it’s taken in the same way:

Zepbound is injected using your injection pen and a fresh needle. Unlike other injections such as vaccinations, these needles are small in size and safe to use at home. You can inject Zepbound into your:

• upper arms (if someone can help you)
• stomach
• upper thigh

It’s best to read the information that comes with your injection and follow the instructions carefully.

Zepbound side effects

The most common side effects of Zepbound (and Mounjaro) include:

• nausea
• vomiting
• diarrhoea
• constipation

These side effects are not usually severe and happen most often when you first start taking tirzepatide. They should decrease over time but if they do not, or you’re struggling to manage them, you should speak with your doctor straight away.

Zepbound and Mounjaro are brand names for the active ingredient tirzepatide when taken for weight loss. They’re both taken alongside a healthy, balanced diet programme and regular exercise as this can provide the best results.

Nearly everything is the same when comparing Zepbound and Mounjaro. The only difference is that Zepbound is the brand name in the USA while Mounjaro is the brand name in the UK. Mounjaro is also available for type 2 diabetes in both countries.

“Tirzepatide at the maximum dose of 15mg per week when taken for 72 weeks can lead to an average weight loss of up to 22.5% from starting weight. If you do not want to take the maximum dose, other maintenance doses still provide effective results. In the same trial, people taking 5mg lost up to 16% of their weight, while those taking 10mg lost up to 21.4%. You’ll get the best results if you follow your treatment regime and Mounjaro diet plan, alongside regular exercise.” – Dr Brenda Ikeji, Medical Editor.

➤ Want to know more about the effectiveness of Mounjaro? Our Mounjaro weight loss week-by-week guide can give you an idea of what to expect during your treatment journey, alongside tips to improve your results.