Mounjaro Golden Dose: Finding Your Maintenance Dose

The Mounjaro “golden dose” is an informal name that’s used to mean two different things: the medication left in your Mounjaro pen after your fourth dose OR the lowest dose where the medication is working effectively for you.

Mounjaro is a weight loss injection that belongs to the glucagon-like peptide 1 (GLP-1) inhibitor family of medications. It works by reducing hunger cues, slowing down how quickly the stomach empties, and regulating insulin levels. Although it’s also used to treat type 2 diabetes, we’ll focus on weight loss in this article.

Taken as a weekly injection, Mounjaro is started at a low dose and gradually increased to a higher maintenance dose. Not everyone will be on the same maintenance dose – 5mg, 10mg, and 15mg maintenance doses are available.

In this article, we’ll explore both definitions of the “Mounjaro golden dose”, including where the name came from, if the “golden dose” is real, how to work out the best maintenance dose for you, and whether it’s safe to use the Mounjaro left in the pen after your fourth dose.

What Is the Mounjaro 'Golden Dose'?

Mounjaro “golden dose” can be used to refer to two different concepts:

1. The small amount of liquid left in a Mounjaro pen after four doses have been administered (also known as the fifth dose)

2. The lowest dose of Mounjaro where someone starts to feel it’s working

When talking about the fifth dose of Mounjaro, “golden dose” is referring to the “extra” medication left over in the Mounjaro pen that can be used at no extra cost (although this is not medically advised).

Relating to the lowest effective dose of Mounjaro, “golden” refers to getting the balance right between effectiveness and cost (as higher doses of Mounjaro often cost more).

Where Does the Term Come From?

The “golden dose” of Mounjaro isn’t an official medical term – it’s an informal name that came about from online forums like Reddit, Facebook groups, and even TikTok. The concept started as a way for people to save money.

Mounjaro pens can be expensive, with the lowest dose pen typically costing £169.95 for a 4-week supply. Prices increased up to 170% at the end of 2025 as the pharmaceutical company that produces the drug, Eli Lilly, increased their UK prices to be in line with international ones.

The “golden dose” started as a way to save a bit of money when taking Mounjaro, either by using medication that would otherwise be wasted (and saving on the cost of another dose) or by using Mounjaro at a lower dose to save money on higher-dose pens.

However, the “golden dose” of Mounjaro isn’t always safe – let’s find out why.

Can I Inject the Liquid Left in the Pen After My Fourth Dose?

Some people use the term “golden dose” to refer to the small amount of liquid left in the Mounjaro pen after the fourth dose of medication is injected.

These pens are designed to administer four set doses of Mounjaro and contain a small amount of buffer medication to allow for priming of the pen. This leftover liquid should not be used – it should be left in the pen and discarded safely.

You can’t be sure how much of this liquid is left and administering it can mean you receive an unknown amount of Mounjaro. This can mean you get too much or too little of the drug.

After the fourth dose, the Mounjaro pen stops working. This means anyone trying to administer the fifth dose would need to extract it with a needle and inject it themselves. This is a safety risk, as it’s possible to introduce bacteria when removing the medication from the pen device. There’s also a risk if using an unsterilised needle to inject yourself or giving yourself an injection if you’re not trained to do so.

It’s not safe to use the remaining “golden dose” of Mounjaro left in the pen after the fourth dose and it’s against manufacturer and medical advice.

Can You Stay on a Lower Dose of Mounjaro?

When taking Mounjaro, a healthcare professional will need to prescribe your Mounjaro pen at a specific dose.

The starting dose is typically 2.5mg injected once weekly for four weeks. After this time, your prescriber will usually increase the dose to 5mg if you’re getting on well with the medication and not experiencing any side effects.

Your Mounjaro dose can be increased up to every four weeks until you reach the maximum maintenance dose of 15mg. Your maintenance dose is the dose you’ll stay at long-term.

Not everyone will increase their dose up to the maximum if they’re happy with the results they see at a lower maintenance dose.

However, in clinical trials, people on the highest maintenance dose lost the largest amount of weight. After 72 weeks on the medication, participants taking 15mg of Mounjaro lost an average 20.9% of their bodyweight compared to 15% in the group taking 5mg.

What Dose Do Most People Settle On?

The maintenance dose that people settle on varies from person to person. The standard maintenance doses recommended by the manufacturer are 5mg, 10mg, and 15mg.

When considering the most appropriate maintenance dose, your prescriber will consider things like:

• Other medications you take

• Any medical conditions you have

• Your BMI

• How much weight you want to lose/your weight loss goals

• Your budget

• How well you respond to lower doses of Mounjaro

• Whether you’re experiencing any Mounjaro side effects or have in the past

You can increase your maintenance dose, but you can also decrease it at a later date if you and your prescriber both agree it’s a good idea.

How to Know When You've Found Your Maintenance Dose

As we’ve already mentioned, not everyone takes the same Mounjaro maintenance dose. Some people are on the highest 15mg dose while others take a lower 10mg or 5mg maintenance dose.

The best maintenance dose for you will be the dose where you’re getting good weight loss effects but not experiencing any side effects that significantly impact your life.

It’s up to you and your prescriber to balance side effects with effectiveness when choosing a maintenance dose. It may take some trial and error to get things right.

A higher dose may lead you to lose more weight, but it can also come with more severe side effects. If you’re not seeing the results you’re hoping for, it may be a good idea to continue increasing your Mounjaro dose.

However, if you’ve experienced side effects while taking Mounjaro, they may get worse at a higher dose. In clinical trials testing Mounjaro as a type 2 diabetes treatment, individuals taking a higher maintenance dose of Mounjaro (10mg or 15mg) were more likely to have to stop treatment due to side effects than people taking the lowest 5mg maintenance dose.

Is Staying on a Lower Dose Clinically Supported?

Yes, the manufacturers of Mounjaro recommend 5mg, 10mg, and 15mg as maintenance doses for weight loss. This means all three doses are suitable to take for longer-term weight management.

People taking higher maintenance doses tend to lose more weight, but people on lower doses of Mounjaro can still lose a significant amount of weight.

In clinical trials, people taking 5mg of Mounjaro a week lost an average 15% of their starting weight. This is significantly more than people taking a placebo (non-active) injection who lost an average 3.1%.

What Happens If You Reduce Your Dose?

You should only change your Mounjaro dose after a discussion with a healthcare professional. They’ll be able to prescribe a new pen for you at a lower dose and can advise you on how much to reduce your Mounjaro dose by.

To change dose, you should use a different dose pen rather than trying to deliver a lower dose from your existing higher-dose pen. Trying to give yourself a smaller dose from a higher-dose pen comes with the risk of not knowing how much of the drug you’ve received. You can also damage the pen and increase the risk of infection if you’ve tampered with your Mounjaro KwikPen.

Once you start taking a lower dose, you may notice that any side effects you’re experiencing improve. You might also find you’re not losing weight as quickly as before, and some people report feeling hungrier again.

It’s a good idea to give your body a few weeks to adjust to any new dose before considering any further dose changes.

If you’re thinking about changing your Mounjaro maintenance dose or have any questions about your weight loss medication, feel free to contact the Quick Meds team. Our experienced staff are always happy to offer advice.

Fill out an online weight loss consultation for personalised advice on weight loss medication, help changing your Mounjaro dose, or information about alternative weight loss treatments.