Origin of expression 'Doctors orders, no 9'?

Question

This is an expression used by bingo callers when the number 9 comes up

Answer 1

in the army during the war if you reported to the MO you were experiencing constipation he would always order a number 9 which was the tablet used to relieve the symptom!! so hence doctors order no 9

Answer 2

The origin of the expression "Doctor's Orders,No 9" is as follows.
It was a pill called the "Number Nine" which was prescribed for numerous ailments by British Doctors during the Second world War.
If you look at the link below it will give you the origins of all the 90 numbers.

Answer 3

I always thought it was because a woman was under the care of the doctor for her pregnancy - 9 months

Answer 4

The two answers above about the Army Medic are correct.

Answer 5

Probably from the song from back in the 1950's or 60's, "Love Potion Number Nine".

That's my theory, anyway.

Answer 6

For some obscure reason, listening to your chest, doctors used to say, 'Say 99'.