Mounjaro

In the UK, Mounjaro® (tirzepatide) is a prescription-only injectable medicine licensed for both managing type 2 diabetes and for weight management in adults with obesity or who are overweight with weight-related health issues. It is intended to be used in conjunction with a reduced-calorie diet and increased physical activity.

Mounjaro® has a unique dual-action mechanism. It activates two different receptors in the body: the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors. By stimulating these receptors, it helps regulate appetite by increasing feelings of fullness and reducing hunger. It also slows down stomach emptying. This combined action helps people eat less, which contributes to significant weight loss.

The most common side effects of Mounjaro® are gastrointestinal issues, such as nausea, diarrhoea, vomiting, and constipation. Other common side effects include decreased appetite, indigestion, and abdominal pain. While most of these are mild to moderate and decrease over time, serious side effects can occur. These include pancreatitis, severe digestive issues, kidney problems, gallbladder problems, and a potential risk of thyroid C-cell tumours.

Adults (18+) with a BMI ≥30, or ≥27 with a weight-related condition (e.g., hypertension, dyslipidaemia, sleep apnoea, prediabetes/type 2 diabetes) may be considered after an online clinical assessment. Suitability depends on your medical history, medicines and treatment goals.

Tirzepatide may be unsuitable if you have a history of pancreatitis, severe gastrointestinal disease (including gastroparesis), certain thyroid problems, severe kidney impairment, or if you are pregnant or breastfeeding. Always disclose your full medical history and all medicines during your consultation.

It is a once-weekly injection. Most people start at 2.5 mg weekly for at least 4 weeks, then step up in 2.5 mg increments (e.g., 5 mg, 7.5 mg, 10 mg, 12.5 mg, up to 15 mg) at intervals of ≥4 weeks based on effect and tolerability as advised by your prescriber.

Appetite changes can appear within the first few weeks. Meaningful weight change typically becomes visible after 4–8 weeks and continues as the dose is gradually increased alongside diet and activity changes.

Results vary, but clinical trials of tirzepatide alongside lifestyle changes have shown substantial average weight loss over several months. Your outcome depends on dose, adherence, nutrition, activity levels and individual response.

They are different medicines. Wegovy®/Ozempic® contain semaglutide (GLP-1 only). Mounjaro® contains tirzepatide, which targets both GLP-1 and GIP receptors (a ‘dual-incretin’).

Yes–many patients switch under clinical supervision. Your clinician will advise washout timing, the safest starting dose on the new medicine and how to manage side effects during the transition.

Take the missed dose as soon as you remember if it’s within 4 days (96 hours) of the scheduled time. If more than 4 days have passed, skip the missed dose and take your next dose on the usual day. Do not take two doses within 3 days of each other.

Inject subcutaneously (under the skin) into the abdomen, thigh or upper arm. Rotate injection sites each week to reduce irritation. Do not inject into tender, bruised or scarred areas.

Yes, your order includes sufficient compatible pen needles for treatment. Use a new needle each time and dispose of used needles in a sharps container as advised.

Seeing a small amount of liquid remaining can be normal—the pen is designed to deliver a fixed dose. Do not attempt a second injection to ‘use it up’. If you’re unsure the dose was delivered, contact our team for guidance.

Eat smaller, slower meals; choose bland, low-fat foods; sip water frequently; avoid alcohol and heavy meals near dosing; and remain upright after eating. If nausea, reflux or constipation persist, speak to your prescriber—dose adjustments or supportive medicines can help.

Moderation is advised. Alcohol can worsen stomach side effects and, if you have diabetes or take certain medicines, may increase the risk of low blood sugar. If you choose to drink, do so sparingly and with food.

During dose initiation and for 4 weeks after each dose increase, tirzepatide can reduce the absorption of oral contraceptives. Use a barrier method (e.g., condoms) for 4 weeks after starting and after every dose step-up. Non-oral methods are not affected.

No. Do not use tirzepatide if you are pregnant or breastfeeding. Stop the medicine and speak to your clinician if you become pregnant or are planning pregnancy—additional washout time is usually recommended.

It may be used alongside other diabetes medicines under medical supervision. If you take insulin or a sulfonylurea, your clinician may need to adjust doses to reduce the risk of hypoglycaemia. Do not combine tirzepatide with another GLP-1 agonist.

Pre-filled pen (single-dose) and vial (single-dose): 2 years shelf life before use. Mounjaro may be stored unrefrigerated for up to 21 cumulative days at a temperature below 30°C, after which the pre-filled pen or vial must be discarded.

Pre-filled pen (KwikPen, multi-dose): 2 years shelf life before use. After first use, store unrefrigerated at room temperature below 30°C. The pre-filled KwikPen must be discarded 30 days after first use.

Source: RxReasoner

Many patients can fast safely with planning—dose timing does not have to align with meals. Prioritise hydration during non-fasting hours, choose gentle, lower-fat foods, and discuss individual risks with your clinician, especially if you have diabetes.

Some people experience increased appetite and weight regain after discontinuation. Building sustainable nutrition, activity and behavioural habits—and discussing a maintenance plan with your clinician—can help preserve results.

A balanced, calorie-reduced diet rich in lean protein, fibre, vegetables and whole grains works well. Many patients find 3 modest meals (or 2–3 structured meals with a planned snack) and mindful eating strategies reduce ‘food noise’. Your care team can tailor a plan.

Yes—aim for a mix of resistance and aerobic training. If you feel light-headed or nauseous post-dose, opt for lighter sessions and stay hydrated. Regular movement supports fat loss and helps maintain muscle.

If you have severe or persistent abdominal pain (especially with vomiting/fever), signs of dehydration, or symptoms of pancreatitis or gallbladder disease, seek urgent medical attention. For milder stomach symptoms, follow the self-care tips and contact us if they don’t improve.

Temporary hair shedding has been reported by some people during rapid weight loss from any cause. It usually settles as your weight stabilises and nutrition is optimised. If concerned, speak to your clinician.

Most people remain on each step for at least 4 weeks. Your clinician will extend a step or pause escalation if side effects persist, and may reduce dose once you reach a sustainable maintenance plan.

Tirzepatide is licensed for weight management based on BMI and clinical criteria rather than specific conditions like PCOS or menopause. If you meet eligibility criteria, your prescriber will consider your full health picture when recommending treatment.

Place used needles in a sharps container immediately after each injection. Do not throw loose needles in household waste. Follow local guidance for returning full sharps containers and disposing of empty pens.

Baseline checks and periodic reviews are often recommended—especially if you have diabetes or other conditions. Your clinician will advise any tests needed to monitor safety and progress.

Always list all prescription medicines, over-the-counter products and supplements in your assessment. Tirzepatide can slow stomach emptying, which may affect the absorption of some oral medicines—your clinician will advise if timing adjustments are needed.

No. It is a once-weekly injectable ‘dual-incretin’ medicine (GIP/GLP-1 receptor agonist). It reduces appetite and improves fullness by acting on gut-brain hormone pathways rather than stimulating the nervous system.

Complete our secure online consultation. A UK-registered prescriber will review your answers and, if suitable, issue a private prescription. Your medicine is then dispensed by our partner pharmacy and delivered discreetly to your address.