Starting weight loss injection: why your first pen must be the starter dose

If you are new to Mounjaro or Wegovy, your first pen must be the 2.5mg/0.25mg starter dose, regardless of the strength you ordered or think you should start on. This is a clinical requirement, not a stock issue or opinion. Once you have done a month on this strength, you can move up to the next level up.

Who this applies to

This article applies to patients ordering weight loss injections for the first time, including patients switching to Mounjaro from Wegovy. If you have used Mounjaro before, whether with another supplier or a certain strength but had a break this is still the rule. As this is what has been deemed safe from our doctors since Mounjaro effects you differently from Wegovy.

Why the first pen must be The starter dose. 

Mounjaro works by binding to receptors in your body that affect appetite and blood sugar. Starting at a low dose gives your body time to adjust. Higher doses without that adjustment period are much more likely to cause side effects (nausea, vomiting, abdominal discomfort) and the medication itself may not work as well.

If you have ordered a higher dose by mistake

If you placed an order for a higher strength (5mg, 7.5mg, 10mg or above for Mounjaro or 0.5mg, 1mg, 1.7mg for Wegovy) and have not used this medication before, we will need to amend your order to starter dose before it can be dispatched.

To do this:

1. Let us know you are happy for us to amend the order to 2.5mg - We may email you this query initially for you to reply with the approval but you can also email us first. 
2. We will adjust the order so it can be processed and dispensed.
3. We will refund any difference in price back to the card you paid with. Refunds typically take 3 to 5 full working days.

If you would prefer to cancel the order instead, that is also fine. Let us know why and we will cancel and refund.

What happens after the first month

If you are not feeling any desired effects after four weeks, then you can move up to the next level but please ensure you are evaluating your habits first. Drinking plenty of water and eating plenty of protein. If all your habits are sufficient and you have no side effects you can move up in dose. If you are experiencing side effects, it is most likely that one of your habits is causing this and it is important to amend this before making the medication stronger. 

Common scenarios

• You have ordered 5mg as your first Mounjaro pen or 0.5mg as your first Wegovy pen. We will contact you to confirm you are happy to amend the order to the starter dose \- The doctor will not prescribe a higher dose unless you have evidence of being on the 2.5mg the four weeks before.
• You are switching from Wegovy to Mounjaro. Mounjaro is treated as a new medication, so you start at 2.5mg even though you were on Wegovy.
• You have used Mounjaro before, took a break, and want to resume. See our switching and "coming off" articles for the rules on resuming. after a 2-week gap it is always a 2.5mg dose as your body is no longer used to the medication. 

What to do next

If we have contacted you about amending your order to 2.5mg/ 0.25mg, reply confirming you are happy for us to do so. If you have not yet ordered, choose 2.5mg/0.25mg as your first Mounjaro/Wegovy pen so the order moves straight through and avoids delays. There is no alternative to this without evidence of being on this strength initially in the last 4 weeks.

Still need help?

See our Contact us article for the best way to reach our team.