A specialist in neurological diseases on Wednesday urged people to look out for lesser-known symptoms of Parkinson's.

At a press conference held a week ahead of World Parkinson’s Disease Day, Dr Shirley Pang, chairwoman of the Hong Kong Movement Disorder Society, said an estimated 12,000 people in the SAR suffer from the condition, with the number expected to grow as the city's population ages.

Pang said people should be aware of symptoms besides commonly-known problems such as tremors.

“Most people can tell that things like tremor or slowness are symptoms of Parkinson's. But I think increasingly, it is recognised that there are very important non-motor symptoms in Parkinson's disease as well,” she said

“For example, the very common ones are constipation… reduced sense of smell. Also, very often, they have sleep disorders, for example, acting out their dreams when they sleep, or insomnia, or daytime sleepiness… Depression and anxiety are also very common non-motor symptoms of Parkinson's disease.”

Pang said there is no specific test for revealing whether someone has Parkinson’s and diagnosis really depends on a doctor's examination.

“We ask for symptoms that the patient may not have been aware of. So if the patient comes because of constipation and dream enactment… I might ask the patient, do you feel that your movement has become slower? Or do you feel that your walking is not as good as before? So that's the history part," she said.

“And then the physical exam is also very important, because sometimes the motor symptoms are mild and the patient may not even be aware of them.”

Pang explained that there’s an "on-time” and “off-time” for Parkinson’s disease patients.

“Parkinson's disease patients feel worse when their brain dopamine level is low. And the way we treat Parkinson's disease is to give dopamine. So ‘on-time’ is when the patients have good dopamine levels in the brain and they have a good functional level. When the medication wears off and the brain dopamine level falls, the patients may not be able to move as well as before. So it's like they're coming off,” she said.

Pang added that a new generation of drugs that better help to stabilise dopamine levels would probably be added to the public hospital drugs formulary soon.