ringing in the ear

My friend has ringing in the ear all the time can you tell me anything
that he can do to stop this ringing.

thanks

this condition is called tinnitus. checkout below link for more details:

http://homeremediesforyou.com/Tinnitus

Ringing in ear i.e tinnitus is often noticeable when the surroundings is quieter like at night when you go to bed. Any noise in the room, like a humidifier, dishwasher or white noise machine can help mask tinnitus and make it less irritating.

Get enough rest. Try to sleep with your head propped up in an elevated position. This decreases head congestion and noises may become less
noticeable.

Avoid alcohol, smoking, caffeine and loud sounds.