The 'standard' anti-wrinkle injection dose is usually wrong

Almost every patient who sits down in my clinic asks some version of the same question: how many units do I need? The honest answer is that the number printed in the product literature is rarely the right one for you.

Where the 'standard' dose actually comes from

Anti-wrinkle injections are a prescription medication, and like any prescription medication, the manufacturer had to get approval from regulators such as the FDA and the EMA before it could be sold. To get that approval, they had to state a therapeutic dose in the documentation — one number, one size, intended to work for the whole population.

That number is a regulatory necessity, not a clinical recommendation tailored to you. It's the dose that gets a medicine approved, not the dose that gets you the best result.

It also explains something patients find genuinely confusing about price. If the dose isn't standard, a flat per-area rate can't really be standard either — what you are paying for is the assessment and the judgement, not a fixed number of units. I've set out what treatment actually costs at our Dublin clinic, and what drives the differences you'll see quoted around the city, in my guide to anti-wrinkle injections in Dublin.

We don't dose blood pressure medication this way — why would we dose this differently?

Think about how we treat something as ordinary as high blood pressure. Some patients need a small dose of their medication. Others need a much bigger one. Nobody would suggest giving every patient with high blood pressure the exact same dose regardless of their size, their physiology, or how strong their muscles are.

The same logic applies to frown lines. It doesn't make sense that every single person in the population, with entirely different muscle strength and facial anatomy, would need the exact same dose to treat the same area. Yet that's effectively what the 'standard' dose assumes.

Start minimal, like seasoning a dish

In my clinic, I work the other way round. To figure out the right dose for someone, you start with a minimal amount — the way you'd put a minimal amount of salt into a dinner. You can always add more later. You can't take it back out once it's in.

That minimal starting dose is a beginning point, not a final answer. Everyone's muscles respond differently, so the only way to know what's right for you is to see how your own face responds first.

Why the two-week review with photos matters

These injections take roughly two weeks to reach their full effect, so that's when I bring patients back in for a proper review — with photos, so we can actually compare movement rather than relying on memory. That review is where the real dosing decision gets made, not on the day of the initial treatment.

• Treat with a minimal, considered starting dose
• Wait the full two weeks for the injections to take effect
• Review with photos to assess how much movement remains
• Adjust from there, specific to that individual's response

The goal is natural movement, not a frozen face

This is the part I think gets lost in a lot of aesthetic medicine: the goal was never to switch the muscle off completely. It's to make the movement more natural, so that you're not left with deep lines etched in when your face is at rest, but you can still frown, still smile, still look like yourself. A face that doesn't move at all isn't the sign of a well-dosed treatment — it's usually the sign of a dose that was never individualised in the first place.

Common questions

Because that dose was set for regulatory approval across an entire population, not for your specific muscles. Using it as a default, rather than a starting point, is how so many people end up either under-treated or over-frozen.

No — it means we find your correct dose safely. You can always top up at the two-week review if some movement remains that you'd like softened further; you can't undo an excessive dose.

Because that's how long the injections take to reach their full effect, and photos let us objectively judge how much natural movement is left, rather than guessing from how the face feels.

Related at Amara

• Anti-wrinkle injections
• Anti-wrinkle injections: the classic areas, and what's beyond them

About Dr Paul

I'm Dr Paul Munsanje — a medical doctor with over 17 years in aesthetic medicine, running a doctor-led clinic across Dublin, Warsaw and Marbella. My work is built on facial anatomy, precision and restraint: treating where it genuinely helps, and just as readily talking you out of what you don't need. This journal is where I write down honestly what I tell my patients.