Yes, tinnitus IS incurable. Currently.
The causes of tinnitus are not yet understood so any attempts to "cure" it are not going to work. There are, however, options for management of it.
Some tinnitus is associated with medical conditions and treating those conditions could help the ringing. Some people can develop serious depression from the condition and it is important to address that if that is you. It is so much more complicated than "my ears are ringing because the guitar player won't turn down". Do your homework from reputable sources. A lot of audiologists may offer "tinnitus management", but they may just have hearing aids that have the programs on it. If it is bad enough to be seeking treatment, it is worth it to try to find somebody that is a bit more invested in the condition, but that is just my editorial thought.
I am an audiology student that is interested in focusing on tinnitus and noise induced hearing loss. "Tinnitus" comes in several forms which can make zeroing in on the cause even more challenging. We all get that brief, 20 or 30 second ringing in one ear that seems to come out of nowhere, but that goes away. If your ears are ringing after a concert, you've done damage to the mechanism even if it goes away the next day. That is "temporary threshold shift" and if you keep at it enough, one day it isn't going to go away. That's a post for another day.
The big points for now:
1. Tinnitus occurs in the brain. There is no external sound source and hearing loss is usually associated with it.
2. Supplements aren't going to fix it. Please save your money on bottled placebos and go see an actual doctor. Ear, Nose and Throat docs are a good starting point. They may send you to an audiologist for evaluation and then management, but you need medical clearance to be sure that it isn't something serious.
3. Sound is your best friend. White noise machines, radios, fans...whatever you need to distract you from that ringing. Since you can't make it go away, management involves masking the sound, distracting your brain from focusing on it and counseling to work on coping with the sound.
4. Hearing aids often have tinnitus management programs. Substantial progress can be made with hearing aids, but they are expensive. Sometimes, if you have a hearing loss and could benefit from hearing aids, just getting them can be sufficient to mask the ringing. Otherwise, some people get them more for the management program which is a type of noise generator that is customized to the pitch of your tinnitus. Hearing aids are more successful if the tinnitus is mild or moderate.
5. Some tinnitus is the brain's way of saying "wait a sec...why aren't I getting 3800 Hertz (or whatever the frequency/frequencies in question)?" It is thought that the brain is compensating for not getting signals at certain frequencies by generating them. Tinnitus therapy involves giving the missing sounds back to the brain to see if it can be appeased, or at least fooled.
Something to remember is that tinnitus that is ONLY in one ear needs to be assessed by a medical doctor. The auditory system loves symmetry and if something is only happening on one side, it may not be a problem but it is best to get that cleared by a doctor "just in case". A possible exception is if the ringing sounds like your pulse. In that case, it is more concerning if that is in both ears and needs to be cleared by a doctor.
There's some good general musician's hearing info here: [Invalid or Expired Link Removed]
It is thought that about 50 million people in the USA have tinnitus. It is no wonder so many hucksters have jumped on the herbal supplement or natural oils bandwagon. If you put drops/oils in your ear, you'll have a shiny eardrum and a greasy pillow but that's about it. If it did find a way to your auditory cortex where the ringing is though to originate, then you have a lot more to worry about than the ringing.