Tirzepatide is a once-weekly injection into the fat layer of the abdomen, thigh or upper arm. Keep the same day each week, rotate the site, and never adjust the dose yourself.
Before your first injection
You should be shown how to inject in person by your care team, and given the chance to practise before doing it alone. Do not rely solely on written instructions or a video.
Choose an injection day that fits your routine and keep it consistent. Many patients pick a day when they are less busy, since the hours after a dose increase can be the least comfortable.
Have a sharps container ready before you start. Needles must never go into household waste.
Where to inject
The medicine goes into the fat layer just under the skin, not into muscle. The three usual sites are the abdomen (avoiding the area immediately around the navel), the front of the thigh, and the back of the upper arm.
Rotate systematically rather than using the same spot every week. Repeatedly injecting one area can cause lumps, irritation and inconsistent absorption.
Avoid injecting into skin that is bruised, tender, red, hard or scarred.
Patient outcomes from supervised programmes at our clinic, published with consent and with faces obscured for privacy. Individual results vary.
Technique that reduces discomfort
Let the pen sit at room temperature for a short period before injecting. Cold medicine stings noticeably more, and this single step makes the biggest difference for most people.
Clean the site and let it dry. Pinch the skin gently if you were shown to, hold the pen at the angle demonstrated, and keep it in place for the full count your team specified so the full dose is delivered.
The needle is very fine. Most patients report far less discomfort than they anticipated.
Storage and handling
Pens require refrigeration within a specified temperature range and must never be frozen. A frozen pen is discarded, not thawed and used.
Once removed from the fridge there is a limited window during which the pen remains usable at room temperature. Your team will give you the exact figures for your product.
Keep pens in their original carton, away from light, and out of reach of children.
Travelling with your medicine
Use an insulated pouch with a cold pack rather than placing pens directly against ice, which risks freezing them.
Carry them in hand luggage, never in checked baggage, where hold temperatures can destroy the medicine. Keep your prescription with you.
Check airline rules on carrying needles, and pack them in a way that satisfies security requirements.
If you miss a dose
Follow the specific guidance your doctor gave you when prescribing rather than guessing. Do not double the next dose to catch up, which reliably produces significant side effects.
If several weeks have been missed, contact your team before restarting. You may need to step back down the ladder rather than resume at your previous dose.
Occasional missed doses happen. Repeatedly missing them is worth discussing, since it may point to a practical problem the programme can solve.
What to record between reviews
Weigh weekly at the same time under the same conditions. Daily weighing mostly captures fluid shifts and will mislead you.
Note waist measurement fortnightly, and any side effects along with the day they occurred relative to your injection.
This turns a vague report into useful clinical information, and patients who track well tend to get better-tailored dose decisions.
What never to do yourself
Do not increase or decrease the dose without medical review. Escalation and reduction are both clinical decisions made after assessing tolerance and progress.
Do not share pens or needles under any circumstances, even within a household.
Do not use a pen that has been frozen, left out beyond its window, or is past its expiry date.
Your first injection, step by step
Take the pen out of the fridge and let it sit at room temperature for the period your team specified. This single step reduces stinging more than anything else.
Wash your hands. Check the pen: right medicine, right dose, within expiry, and the liquid clear rather than cloudy or containing particles. Discard it if anything looks wrong.
Choose your site and rotate from last week's. Clean the skin and let it dry fully — injecting through wet antiseptic stings. Attach a new needle if your pen requires one.
Inject at the angle you were shown, hold for the full count your team gave you so the complete dose is delivered, then withdraw and dispose of the needle straight into your sharps container.
Common mistakes to avoid
Injecting straight from the fridge is the most frequent cause of unnecessary discomfort. Injecting into the same spot every week causes lumps and unpredictable absorption.
Withdrawing the pen too early means part of the dose is left behind, which patients often do not realise. Count fully.
Reusing needles risks infection and blunt-needle pain. Using a pen that has been frozen renders the medicine ineffective even though it looks normal.
Rubbing the site vigorously afterwards is unnecessary and can increase bruising. A light press is enough.
Injection anxiety and needle fear
Needle anxiety is common and rarely discussed. It is a genuine reason people delay starting treatment, and it is manageable rather than something to push through alone.
Practical measures help: injecting at the same time each week to build routine, having someone present for the first few, looking away, and using the thigh rather than the abdomen if that feels less confronting.
The needles used are very fine, and most patients report the anticipation is considerably worse than the injection itself.
Tell your care team if this is a barrier. It is a normal thing to raise and there are approaches that help.
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Frequently asked questions
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Can I inject on a different day each week?
Medical disclaimer. This article is general information, not medical advice, and does not replace consultation with a qualified doctor. The medicines discussed are prescription-only and must be prescribed and monitored by a physician. Outcomes vary between individuals. Never start, stop or change a prescribed medicine without medical advice.