Do Redheads Really Require More Anesthesia?

It is pretty fair to say that no one really enjoys getting a cavity filled or going under anesthesia because of a painful surgery, it’s just something we have to do. Although it isn’t fun for anyone, redheads may dread a trip to the dentist’s office a bit more than the average person, and for good reason. Over the years, many have said that a patient’s natural hair color may have an impact on anesthesia efforts. But do redheads really require more anesthesia? Recent studies have been done that show people with naturally red hair often require a higher dosage of anesthesia, and are sometimes resistant to pain blockers, such as novocaine, than their brunette or blonde counterparts.

Making up only 1-2% of the population worldwide, the genetics of a redhead are what makes them such a rarity. Researchers believe a mutation of the gene that causes people to have red hair and fair skin, also has an effect on a person’s sensitivity to pain. The Mc1R gene, which affects hair color, produces melanin in people with blond, black, or brown hair, but a mutation causes it to produce pheomelanin in redheads. This gene is a part of a family of receptors in the brain that include pain receptors, which may be why it affects a redheads tolerance of pain.

Dr. Daniel I. Sessler, an anesthesiologist and chairman of the department of outcomes research at the Cleveland Clinic, said he started studying hair color after hearing many colleagues discuss redheads needing more anesthesia than patients with different hair colors. “The reason we studied redheads in the beginning, it was essentially an urban legend in the anesthesia community saying redheads were difficult to anesthetize,” Dr. Sessler said. “This was so intriguing we went ahead and studied it. Redheads really do require more anesthesia, and by a clinically important amount.”

Researchers believe patients with red hair require about 20% more general anesthesia than the average person, which proves that redheads being harder to anesthetize was not just a myth in the medical community. Another study in 2005, proved that redheads are more resistant to the effects of local anesthesia, such as the numbing drugs that are often used by dentists. It is possible that people with dark skin, eyes, and hair may produce more melanin than normal and in turn will also require more anesthesia. So the next time you hear your redheaded friend complaining about a routine trip to the dentist, you’ll know why!