If you plan on highlighting or bleaching your hair for the first time, ask yourself if you've ever done a patch test.
If the answer is "no", you may be at risk of suffering adverse reactions that could leave your scalp itchy, painful and tender. This typically occurs as a result of allergic reactions to chemicals in hair dye, say hair and scalp experts.
Trichologist Leonica Kei, 50, from Philip Kingsley Trichological Centre in Orchard Road, said that it is important to check beforehand if one's scalp is suitable for dye or bleach treatments.
While hair salons can do a patch test for customers, five salons my paper spoke to said they do not do it unless asked.
Recently, my paper columnist Clara Chow, 35, dyed her hair at a salon and did not think to have a patch test done beforehand. She ended up with more than she had bargained for.
"I didn't think I needed one (a patch test), and I thought they (the hairdressers) knew what they were doing, because I stressed many times that my skin and scalp are very sensitive," she said.
Shortly after her dye treatment, Ms Chow noticed that her locks were falling out. Left with few options, she decided to shave off her hair about two or three weeks later.
She wrote about her "botak" experience in her Manic Mummy column published in my paper on Sept 24.
Most customers choose not to do the patch test because of the inconvenience, said Mr Juno Ong, 32, the owner of Artica, a hair salon at Far East Plaza.
It takes around one to three days to see if there's any skin reaction.
Customers who know they have allergies may also choose not to do it, choosing to ignore the likelihood of anything going awry, he said.
He added: "Most want to do it (dye their hair), even though their scalp is sensitive."
As one ages, skin on the scalp may become thinner, and this may result in certain hair products causing allergic reactions, even though they did not in the past, said Ms Kei.
She said: "If you've been colouring your hair for more than 10 years, you would probably have a sensitive scalp."
Polytechnic student Jonathan Goh, 18, started sprouting grey hairs on his head when he was 10 and has turned to hair dye to look his age.
Mr Goh has been dyeing his hair every two to three months, for the past four years. He said: "The quality of my hair is definitely affected. My hair is really rough and dry."
The most common complaint was about damage to hair, due to allergies or unsuitable chemicals used.
One complaint relating to hair-dye treatments was lodged with the Consumers Association of Singapore (Case) in the first half of this year.
There were four such reports in the same period last year.
"Consumers, first of all, need to ensure that the chemical being used will be accepted by their scalp," said Mr Seah Seng Choon, executive director of Case.
Highlighting one's hair is the safest way to add colour to the hair without adverse side effects, said Ms Kei.
This is because there is little chance that the chemicals from the dye will come in contact with skin during the highlighting treatment, she added.
More risks are involved in dyeing a full head of hair and bleaching.
As for the types of dye, chemicals are usually used as natural alternatives, such as henna dyes, are limited in colour range.
Ms Kei said she once had a client who suffered burns to the scalp as a result of either bleaching or rebonding treatments.
"The scalp was red and sore, and there was flaking due to the dryness," she said.
Lawyers my paper spoke to said that consumers can sue salons for damages, if allergies due to serious medical conditions flare up.
Criminal lawyer Foo Cheow Ming of law firm Peter Ong & Raymond Tan said: "If it's a serious medical condition, they can sue for damages. The amount of damages awarded would be according to the degree of the injury."
However, the customer would have to prove that the salon was negligent, said Mr Lee Terk Yang, a director of law firm Characterist LLC.
He said: "You've got to prove a causal link between the treatment and the reaction.
"They (customers) will have to prove that the salon was negligent and did not do a patch test."
"You've got to prove a causal link between the treatment and the reaction. They (customers) will have to prove that the salon was negligent and did not do a patch test. "
- Lawyer Lee Terk Yang
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