What the approved New Zealand product information says. Your prescriber decides what applies to you.
This is a summary of the approved New Zealand product information, not a substitute for the leaflet in your pack or for what your prescriber tells you. glp.nz is not a substitute for a clinician and gives no medical advice.
For anything milder, contact whoever prescribed for you before changing or stopping the medicine yourself. Healthline is free on 0800 611 116, and your pharmacist can advise without an appointment.
Most are gastrointestinal, most appear while the dose is increasing, and most settle. They are the reason the dose is stepped up slowly rather than started at full strength.
In the SELECT trial of semaglutide, 16.6% of participants stopped treatment because of side effects, against 8.2% on placebo. Roughly one person in six found them intolerable over four years. Dizziness during dose escalation is the reason the data sheet advises caution with driving in that period.
Eating smaller portions, stopping when full, and avoiding rich or greasy food are what the product information suggests. Nausea usually eases after the first few weeks at a given dose.
The main risk is dehydration. Keep fluids up. If you cannot keep fluids down, that is a reason to call someone rather than wait it out.
Fluid, fibre and movement are the usual first steps. Your pharmacist can suggest something over the counter if it persists.
Talk to your prescriber before changing anything. They may hold you at the same dose for longer, or step up more slowly, rather than moving to the next strength on schedule.
The schedules in the approved New Zealand product information. Your prescriber may vary them, commonly by holding a dose longer if side effects are difficult.
| Wegovy · semaglutide, once weekly | Duration | |
|---|---|---|
| Weeks 1–4 | 0.25mg | 4 weeks |
| Weeks 5–8 | 0.5mg | 4 weeks |
| Weeks 9–12 | 1.0mg | 4 weeks |
| Weeks 13–16 | 1.7mg | 4 weeks |
| Week 17 onward | 2.4mg | Maintenance |
| Mounjaro · tirzepatide, once weekly | Duration | |
|---|---|---|
| Weeks 1–4 | 2.5mg | 4 weeks |
| Week 5 onward | 5mg | Maintenance dose, or step up further |
| If increasing | 7.5mg, 10mg, 12.5mg, 15mg | At least 4 weeks at each step |
Each strength is a separate pen, which is why the price changes as you move up. Current prices for every strength.
In the fridge between 2°C and 8°C. Do not freeze, and do not use a pen that has been frozen. Keep the cap on and out of reach of children. Check the expiry date on the pen.
Once a week, the same day each week, at any time of day, with or without food. If you need to change which day, the product information sets a minimum gap between doses. Check the leaflet or ask your pharmacist.
Under the skin of the abdomen, thigh or upper arm. Rotate the site each week. Not into a vein or muscle.
The CMI says to take it as soon as you remember if it has been only a few days, then continue on your usual day. If your next scheduled dose is close, skip the missed one rather than doubling up. The exact window differs between products, so check your leaflet.
Never share a pen, even with a new needle. Used needles go in a sharps container. Your pharmacy can supply one and dispose of it.
Tell your doctor or pharmacist before you travel so you can plan cold storage. Some pharmacies charge a cold-chain handling fee on delivery for the same reason.
The product information advises against use in pregnancy and breastfeeding: semaglutide passed into milk in animal studies and a risk to a breastfed child cannot be excluded. It should not be used by anyone who has had an allergic reaction to the active ingredient, and should not be combined with another GLP-1 medicine. Tell your prescriber about any other conditions or medicines, there are specific cautions around pancreatitis, gallbladder disease, diabetic eye disease and thyroid history that need a clinician's judgement.