How to take tirzepatide

Weekly injection — the practical guide

Quick read · 5 min

Last reviewed: April 2026Every claim linked to source

Tirzepatide (Zepbound or Mounjaro) is a once-weekly injection you give yourself at home with a pre-filled pen. It can be taken any day, any time, with or without food. The whole injection takes under 10 seconds.

In simple terms:
  • Once a week, any day, any time, with or without food
  • Pre-filled pen — the needle is already attached, no mixing
  • Inject under the skin of the belly, thigh or upper arm
  • Fridge until first use; room temperature for up to 21 days after
  • Missed dose: take within 4 days, otherwise skip to next week

Based on clinical trials · No rankings · Every claim linked to source


The injection, step by step

Most people master this in 2–3 tries.

1
Let it warm up

Take the pen out of the fridge 5–10 minutes before you inject. Cold medicine feels sharper. Never use heat to warm it.

2
Check the liquid

Look through the window. It should be clear and colourless. If it's cloudy, discoloured or has bits in it, don't use it.

3
Pick and clean a spot

Choose belly (at least 2 inches from your navel), front/outer thigh, or back of upper arm. Clean with an alcohol wipe if visibly dirty, let it dry.

4
Remove the cap

Unscrew the cap straight off (about 3 turns). Keep it — you'll use it to cover the needle afterwards.

5
Pinch and press

Pinch a small fold of skin. Push the pen straight in at 90 degrees. Press the button on top of the pen.

6
Wait for the click

You'll hear a click when the needle retracts and the dose is delivered. Hold it in place for 3 more seconds, then pull straight out.

Three safe injection sites
  • Belly (abdomen) — at least 2 inches from your belly button
  • Front or outer thigh
  • Back of the upper arm

Rotate sites week to week so the same spot doesn't get sore or thickened.

Do this
  • Let the pen reach room temperature first
  • Rotate sites (belly, thigh, arm) week to week
  • Listen for the click — that's how you know it's done
  • Pick a consistent day and time each week
  • Store unopened pens in the fridge
Don't do this
  • Reuse a pen — each one is single-use
  • Warm the pen in hot water or microwave
  • Inject into bruised, scarred or tender skin
  • Massage or rub the site after injecting
  • Inject twice in one week to make up

Storage

Fridge before you start, then room temperature is fine.

Before first use
Fridge, 36–46°F
After first use
Room temp OK for up to 21 days
Never
Freeze or leave in the heat

If you miss a dose

Simple rules — no double-dosing.

1
Remember within 4 days of your usual day
Take it as soon as you remember. Resume your normal schedule next week.
2
More than 4 days late
Skip the missed dose entirely. Take the next one on your usual day.
3
Never
Double-dose to catch up. Only one injection per week.

Next step most people take

Based on clinical trials · No rankings · Every claim linked to source

Last reviewed: March 2026

Medical disclaimer: This website is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any treatment.