Redheads have a reputation for being more sensitive and less tolerant.
This apparently extends past their temperament. There have been studies conducted, simply to find out if the rumors were actual fact; that redheaded people were harder to put under anesthetic.
There have been several studies conducted and the fact is, yes.
Redheads are harder to get under than those with darker hair.
It started out as a myth or urban legend, but professionals were curious enough to start conducting studies.
Anesthesia: Not One Size Fits All
Factors such as age and weight come into how much anesthesia is administered.
Other things that must be considered are illnesses, any medication the patient may be taking plus any other types of street drugs that may be in their system.
Also, gender and age will also play a part.
Now, here come the redheads.
Research has been conducted several times, all with the same basic results.
That redheaded people have a different tolerance to pain and in fact, require a bit more anesthesia to get them out for surgery and to keep them from waking up or feeling pain during their procedure.
It’s In The Genes
A continuous body of research shows that people with red hair need larger doses of anesthesia for having procedures done at the dentist or surgery.
It also shows they are often are resistant to local pain blockers like Novocaine.
Researchers conducting these studies believe that redheads are more sensitive to pain due to a mutation in a gene that affects hair color.
People who have brown, black or blond hair, contain the gene for the melanocortin-1 receptor and produce melanin.
However, a mutation in the MC1R gene causes the production of a substance called pheomelanin that results in red hair and fair skin.
This MC1R gene is part of a family of receptors that also includes pain receptors in the brain.
The mutation in the gene appears to influence the body’s sensitivity to pain.
Redheads seem to be more sensitive to pain, which means they may have a higher tolerance for it. It’s not entirely clear why, but one explanation could be that the MC1R gene is also connected to the hormones that stimulate pain receptors in the brain.
The same mutation that stops the production of one pigment and increases another could also overproduce a pain-related hormone, or perhaps it is that the pigments themselves cause an increase in pain sensitivity.
If the MC1R gene doesn’t function properly, the melanin doesn’t have a receptor site to bind with.
The pigments may then seek other, similar receptors such as the brain’s pain receptors.
If the pain receptor and the pigment don’t really bind, it could overstimulate the brain’s pain response, which could explain the increased need for anesthesia.
Where’s The Research?
A study was conducted at the University of Louisville with 20 women.
10 were redheaded, the 10 brunettes they were in a control group.
All were from 19-40.
All 20 women were given desflurane, which is a common gas anesthesia.
Once the anesthesia had taken effect, the researchers applied electric shocks to all the women.
They used a voltage that was enough that a conscious person would have found quite too much to handle.
If the subject was still able to feel the pain, the dosage of desflurane was increased and they continued to receive shocks until they could no longer feel them.
They concluded that redheaded people needed upwards to 20 % more anesthesia to get them under and keep them there.
More Research is Needed
Geneticists are confident that the MC1R gene is directly related to pain.
The University of Louisville study has shown the first demonstrable link between a phenotype and anesthesia.
Since anesthesia’s effects on the brain aren’t completely understood, further study on the role genes plays in these higher functions could answer questions researchers still have regarding which regions of the brain are responsible for these functions.
A fairly new area that studies how humans react differently to drugs, based on differences in their genes is pharmacogenetics.
This can help identify problem areas such as upping the dosage of general anesthesia to knock out redhead patients which could increase the risk of an overdose.
Future pharmacogenetic research may produce a completely different anesthesia that’s designed specifically for redheads.
This would make anesthesiologists jobs much easier and keep patients safer, as well.
It’s already a dangerous position for the patient and the anesthesiologists as it is, so any research that eases risks would be certainly welcome.