Veteran actor Dick Van Dyke has turned to his fans for help in diagnosing his medical issues after baffling doctors with his health troubles.

The beloved Mary Poppins star, 87, was forced to pull out of an upcoming New York event next week (begs22Apr13) due to fatigue and his representative revealed the lack of sleep was the result of a "yet-to-be diagnosed neurological disorder".

He has been ordered to rest up at his home in Malibu, California until medics can identify the cause of his tiredness, but Van Dyke decided to do something about the mystery himself by reaching out to fans online to ask for their advice.

In a Twitter exchange with devotees on Wednesday (17Apr13), the actor revealed he suffered from "very low blood pressure" and had been battling the illness for some time.

He tweets, "My head bangs every time I lay down. I've had every test come back (stating) that I'm perfectly healthy. Anybody got any ideas? It has been going on for 7 years. I've had every test you can think of (CAT Scan, Mri, Spinal tap etc)".

Fans recommended he be tested for hearing and balance disorder Meniere's disease or tinnitus, while one concerned devotee suggested he book an appointment with a specialist chiropractor, only for Van Dyke to declare, "I don't believe in them".