Weight loss injections & the contraceptive pill: what you need to know
If you’re considering or already using weight loss injections like Wegovy, Mounjaro, Ozempic or Saxenda, it’s completely normal to have questions about how these treatments might affect your contraception, especially if you rely on the pill.
With so much information out there, it can feel overwhelming to know what’s safe and what isn’t.
Understanding how these medications interact with different types of contraception is important. Some weight loss injections can change how well the pill works, while others don’t cause any issues at all.
And because these treatments aren’t safe to use during pregnancy, making sure you’re properly protected is key.
In this guide, we’ll clearly explain how each weight loss injection can affect your contraception, highlight when you might need extra protection, and show you how we can help you stay safe and supported every step of the way by getting your contraceptive pill for free (if you aren’t already!) by using the NHS Pharmacy Contraceptive Service[1].
Wegovy, Ozempic, Saxenda & the pill: is your contraception still effective?
If you’re using Wegovy, Ozempic or Saxenda to help with weight loss, it’s natural to wonder if your contraception will still work as it should.
The good news is that, for most women, medicines like Wegovy don’t interfere with how the pill works[2]. You can continue taking your usual contraceptive pill without needing extra precautions.
This is because they are a type of medicine known as a GLP-1 receptor agonist, and they don’t directly interact with how the pill works in your body.
However, it’s important to be aware of possible side effects. If you experience vomiting or diarrhoea within a few hours of taking your pill, your body might not absorb it properly. In these cases, it’s safest to use condoms or another backup method for the next seven days, just in case.
And remember, none of these medications are safe to use during pregnancy, so keeping up with effective contraception is essential to ensure you don’t fall pregnant while using your weight loss injection.
If you’re ever unsure, don’t hesitate to ask your pharmacist for advice.
Mounjaro and the contraceptive pill
Mounjaro is a newer weight loss injection that works a little differently from the others, as it’s both a GIP and GLP-1 receptor agonist.
One important thing to know is that Mounjaro can slow down how your body absorbs medicines taken by mouth, including the contraceptive pill. This means the pill might not protect you from pregnancy as reliably as usual.
To stay safe, you should use an extra method of contraception, like condoms, for at least four weeks after starting Mounjaro or if your dose increases. Alternatively, you might want to consider switching to a non-pill method, such as the implant, injection or coil, which aren’t affected by Mounjaro.
We understand this might feel like a hassle, but it’s the best way to ensure you’re fully protected. If you need help choosing the right contraception, our pharmacy team is always here to support you.
Why you shouldn’t get pregnant on weight loss injections
If you’re considering starting a family soon, it’s important to know that weight loss injections like Wegovy, Ozempic, Saxenda and Mounjaro aren’t safe to use during pregnancy. These medications haven’t been tested in pregnancy and could potentially harm your baby.
If you do become pregnant while using any of these injections, stop the medication straight away and speak to your doctor or pharmacist as soon as possible. For your health and your baby’s, it’s best to use reliable contraception and wait until you’ve finished your course of treatment before trying for a baby.
Additionally, there’s limited research on the safety of weight loss injections while breastfeeding, so most healthcare professionals recommend avoiding these medications during this time, as it’s not yet clear whether they can pass into breast milk or affect your baby.
Best contraceptive pill alternatives if you’re using Mounjaro
If you’re on Mounjaro, it’s a good idea to think about non-pill contraceptive options. These methods aren’t affected by Mounjaro and offer excellent protection:
- Contraceptive implant. This is where a small rod is placed under the skin of your arm. It lasts up to three years.
- Contraceptive injection. This is given every 8 -13 weeks, depending on the type.
- Hormonal or copper coil (IUD). This is placed in your womb, and lasts from 3 to 10 years.
- Contraceptive patch or vaginal ring is changed weekly or monthly and is easy to use.
Each method has its pros and cons, and what’s right for one person might not suit another.
The pill vs. non-pill contraceptives: what’s right for you on weight loss injections?
| Method | Safe with Wegovy, Ozempic & Saxenda | Safe with Mounjaro | Notes |
|---|---|---|---|
| Combined pill | Yes | No (use extra) | Use extra protection with Mounjaro (e.g. condoms) |
| Progestogen-only pill | Yes | No (use extra) | Use extra protection with Mounjaro (e.g. condoms) |
| Implant | Yes | Yes | Highly effective, long-lasting |
| Injection | Yes | Yes | 8-13 weeks of protection |
| IUD (hormonal/copper) | Yes | Yes | Up to 8 years of protection |
| Patch/ring | Yes | Yes | Good for those who forget pills |
| Condoms | Yes | Yes | Also protects against STIs |
How the NHS Pharmacy Contraceptive Service (PCS) can help
The NHS Pharmacy Contraception Service (PCS) makes it easy to access the contraceptive pill in your local or online pharmacy, offering confidential consultations and free supply for eligible patients without needing a GP appointment or a visit to a sexual health clinic.
To use this service, you need to be looking to start the contraceptive pill or for a repeat supply. For the combined pill, you must have started your periods and be under 50 years old. For the progestogen-only pill, you must have started your periods and be under 55.
If you're using weight loss injections like Wegovy, Ozempic or Saxenda and you meet the above requirements, getting your contraceptive pill through this free service will help prevent pregnancy while you’re on your treatment journey.
However, if you're on Mounjaro, the pill might not work as well for you, and you might need a different contraceptive option, as we talked about earlier.
Our pharmacists are here to advise you on the best choice for your needs, so you can stay protected and confident during your weight loss journey.
