Rather than extra tax which effects everyone who is working, why not a charge of say £20 to see your doctor and a daily charge for hospital stays?
Those who presently qualify for free prescriptions should be exempt so only those who use the NHS and can afford it would pay.
I have only been in Hospital for 5 days (hernia op) in 63 years and have only needed a doctor 2 times in the last 10 years so I would have been well out of pocket by a universal NHS Tax.
If income tax was increased to fund the NHS how long do you think it would be before the cash raised was 'diverted' to another area of government spending? Could we trust the government to make sure the extra was only ever used for the NHS. ( A lot of which has already been 'privatised' by the back door way)
Private health is a fairer system today, considering all the extraneous NHS do. Boobs, gender benders, free treatment for all whether or not residents.