What the… OW! Why Injections On The Left Hurt More

It’s a truth universally acknowledged among aesthetic practitioners — but rarely disclosed to patients — that treating the left side of the face hurts more than the right. What the… OW! Why should this be? Here are a few thoughts.

Seriously, does the left side hurt more?

‘Absolutely! I’ve seen this over time and frequently have patients mention it to me,’ says the aesthetic practitioner Dr Ben Taylor-Davies, clinical director of The Face Clinic, Edinburgh. ‘It’s also something I’ve noticed myself when having my own treatments! We don’t 100 per cent know why this is the case, and I don’t specifically mention this to my patients as we know that anticipation of any discomfort can potentially make it worse. But, if a patient asks why the left side seems to be more uncomfortable, then it’s something I’d discuss with them.’

Why is one side more sensitive?

I’ve asked a few practitioners over the years, and no one has a concrete answer, apart from pointing out to me that pain is processed and felt differently on different sides of the body. I’ve had a grub around for studies about this, and found one published in the December 2009 issue of Neuroscience Letters which showed that right-handed study participants could tolerate more cold pain in their right hands than in their left hands.

There has even been a scholarly article about left/right side pain asymmetry with cosmetic injections in the Journal of Aesthetic Surgery in 2017 (link below), which noted that individual pain scores were significantly different, with ‘pain rated as worse on the L side of the face.’

It helps if we relax…

‘This phenomenon of increased sensitivity on the left side of the face is definitely a thing!’ says Dr Hayley Elsmore, who leads The Courtyard Clinic on the Isle of Wight. ‘I think it is reassuring for patients to know they are not the only ones to experience it and it isn’t anything to do with the procedure, it just hurts more! People relax once they know that!’

‘What we do know is that relaxed patients tend to experience less discomfort and have better clinical outcomes,’ agrees Dr Taylor-Davies. ‘That is why I try to focus on making sure patients are generally relaxed and comfortable for any procedure,’

So, which side should injectors start with?

If the right side is less uncomfortable, surely it’s kinder to start injecting on that side? From a personal perspective, I find that once I know a treatment is going to feel manageable, I stop feeling so stressed about how much it’s going to hurt. ‘I normally start on the right,’ says Dr Elsmore. ‘I find that easier rather than have patients tense for the second half!’

That paper on left/right pain asymmetry came to a rather different conclusion though. From their study they found that ‘when treatments were performed first on the L side, patients rated the overall experience as significantly less painful than when treatments were begun on the R side,’ presumably because it got the worst bit out of the way first. So, the study concluded with the recommendation that practitioners should start their injections on the left.

Dr Taylor-Davies says he starts on the right, because he is right-handed, but is now wondering whether he should begin injecting on the left. I dare say it’s logical, but as a patient who even now, after hundreds and hundreds of injections, still feels every single one, I’d have to add that I prefer the softly-softly right-hand side first!

• This is the article on Left/ Right Pain Asymmetry with Injectable Cosmetic Treatments