What is Mounjaro Kwikpen?

Mounjaro Kwikpen is a once-weekly, prescription-only injection used to support weight management in adults when combined with a reduced-calorie diet and increased physical activity. It is manufactured by Eli Lilly and supplied as a pre-filled pen that delivers four weekly doses.

How does it Work?

Tirzepatide (the active ingredient) activates both GIP and GLP-1 receptors—two naturally occurring hormone pathways involved in appetite and glucose regulation. This dual action can:

Reduce appetite and food cravings
Slow gastric emptying so you feel fuller for longer (this effect may lesson)
Improve the body's response to insulin and lower glucose levels

Who should not use it?

Do not use Mounjaro if you:

Are pregnant, planning pregnancy, or breastfeeding
Are allergic to tirzepatide or any excipients
Have a personal/family history of medullary thyroid carcinoma (MTC) Multiple Endocrine Neoplasia syndrome type 2 (MEN2)

Tell your prescriber before starting if you have or have had:

Pancreas, liver, kidney or gallbladder problems
Severe stomach or gut issues (e.g., gastroparesis)
Diabetic retinopathy
Heart conditions (including rhythm problems or heart failure)
Current use of insulin or a sulfonylurea (these are not used together with Mounjaro in Mederoo’s programme)

Who might be suitable?

Your Mederoo prescriber may consider Mounjaro for adults who meet BMI criteria and are ready to make lifestyle changes:

BMI ≥ 30, or
BMI ≥ 27 with at least one weight-related condition (e.g., prediabetes or type 2 diabetes, hypertension, dyslipidaemia/heart disease, obstructive sleep apnoea, PCOS, osteoarthritis or gout, chronic back pain, fatty liver disease, or a history of gallbladder disease). Suitability is always determined in a clinician-led consultation.

Typical Dosing Schedule

2.5 mg

once weekly for 4 weeks

Then increase stepwise (if tolerated and clinically appropriate) to 5 mg, 7.5 mg, 10 mg, 12.5 mg, up to a maximum of 15 mg once weekly. Your prescriber will individualise the pace of dose increases based on effect and tolerability

How to use the pen (overview)

Inject >once weekly on the same day each week. If changing your dosing day, leave at least 72 hours between doses.
Approved injection sites: abdomen, thighs, or upper arms.
Follow the Patient Information Leaflet (PIL) for full instructions, including pen checks, priming, correct injection technique, and safe needle disposal in a sharps container.

Missed a dose?

If 4 days after the missed dose: take it as soon as possible.
If more than 4 days, skip the missed dose and take the next one on your usual day.
Never take two doses within 3 days of each other. Speak to Mederoo before altering your schedule.

Expected benefits

In clinical studies of tirzepatide for weight management, many participants achieved clinically meaningful weight loss. Higher doses produced greater average reductions, though individual results vary. Sustainable lifestyle change remains essential for long-term success.

Approved injection sites: abdomen, thighs, or upper arms.
Follow the Patient Information Leaflet (PIL) for full instructions, including pen checks, priming, correct injection technique, and safe needle disposal in a sharps container.

Storage and Handling

Unused pens

keep refrigerated 2–8°C; do not freeze. If frozen, discard.

In-use

May be kept at room temperature (up to 30°C) for up to 30 days; keep away from heat. Dispose of each pen after it has delivered 4 weekly doses.

Interactions and special cautions

Mounjaro slows stomach emptying, which can affect absorption of oral medicines.
Additional monitoring may be required with warfarin, digoxin, and other narrow therapeutic index drugs; tell your prescriber about all medicines and supplements.
Using insulin or sulfonylureas alongside tirzepatide increases hypoglycaemia risk—Mederoo does not co-prescribe these with Mounjaro for weight loss.
Oral hormonal contraception: effectiveness may be reduced during titration. Consider switching to a non-oral method or add a barrier method for 4 weeks after starting and 4 weeks after each dose increase. Discuss options with your clinician.

Who might be suitable?

Common

Nausea, vomiting, diarrhoea, constipation, indigestion, abdominal pain, reduced appetite.
These are most frequent during or after dose increases and often settle with time.

Serious

Signs of pancreatitis (severe, persistent abdominal pain that may reach the back, with or without vomiting)
Signs of dehydration (e.g., very dark urine, confusion, dizziness) especially if vomiting/diarrhoea lasts >72 hours or you cannot keep fluids down
Severe allergic reactions (swelling of face/lips/tongue/throat, breathing difficulty, fainting, severe rash)
Visual changes
Symptoms of low blood sugar (more likely if combined with other diabetes medicines)

How does it compare with alternatives?

Other licensed weight-management options include semaglutide (Wegovy), liraglutide (Saxenda), orlistat, and naltrexone/bupropion (Mysimba). Each differs in efficacy, dosing schedule, side-effect profile, and suitability. Your Mederoo prescriber will help select the most appropriate option for your health status and goals.

Obtaining treatment through Mederoo Health

Complete Mederoo’s secure online consultation. A registered prescriber will review your history and decide if tirzepatide is appropriate. If approved, medication is supplied in cold-chain packaging to maintain product quality. Ongoing check-ins, education and lifestyle support are available throughout treatment.

Quick reference (product overview)

Name

Active ingredient

Manufacturer

Legal status

Form

Strengths

Use

Administration

Mounjaro

Tirzepatide

Eli Lilly & Company

Prescription only (POM)

Pre-filled, multi-dose pen (4 weekly doses per pen)

2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, 15 mg

Adults meeting BMI/clinical criteria as assessed by a prescriber

Subcutaneous injection, once weekly

Read before use

Summary of Product Characteristics (SmPC) and Patient Information Leaflet (PIL)

Shared decision-making

Treatment decisions are made jointly between you and your prescriber following a clinical assessment. The prescriber always makes the final call on appropriateness and dosing for your safety.

Expected benefits

Evidence snapshot: tirzepatide vs placebo (SURMOUNT-1)

Participants achieving ≥5% weight loss at 72 weeks: 5 mg – 85.1%, 10 mg – 88.9%, 15 mg – 90.9%, placebo – 34.5%.
Participants achieving ≥20% weight loss: 10 mg – 50%, 15 mg – 57%, placebo – 3%.

Note

Summary of Product Characteristics (SmPC) and Patient Information Leaflet (PIL)