Redheads, pain and the anesthesia story

You may have heard that redheads need more anesthesia. It sounds like a myth, but it's one of the few redhead stories with real research behind it. And the full picture is surprising.

Study 1: more anesthesia (2004)

Researchers at the University of Louisville, led by Edwin Liem, compared 10 natural redheads with 10 dark-haired women. Published in the journal Anesthesiology, the study found that redheads needed about 19% more desflurane, a common anesthetic gas, to reach the same effect. Nine of the ten redheads carried MC1R variants.

Study 2: numbing works less (2005)

The same team then showed that redheads were more sensitive to cold and heat pain, and that lidocaine injected under the skin, the classic local anesthetic, worked less well on them.

Study 3: fear of the dentist (2009)

A study of 144 people published in the Journal of the American Dental Association found that people with MC1R variants reported more dental anxiety and more fear of dental pain, and were more than twice as likely to avoid dental care, even after taking general anxiety into account.

Study 4: plot twist (2021)

In 2021, a team at Massachusetts General Hospital published a study in Science Advances showing that red-haired mice actually had a higher pain threshold for some types of pain, and responded better to opioid painkillers. So redheads are not simply "more sensitive". It depends on the type of pain and the type of medicine.

My advice

Just tell your doctor or dentist. It's a documented thing, and a good professional will take it seriously. There's no shame in saying "I'm a redhead, and numbing doesn't always work great on me."

Tough on the outside, extra sensitive on the inside. Sometimes literally.

This article is for general information, not medical advice. Always talk to a health professional about your own situation.