Loud Noise Treatment

Since permanent tinnitus tends to start a couple of days after a massive noise event and can be best treated right after a noise event it's important to get medical help for treatments such as Prednisone ASAP. If your ears hurt, had ringing, or went deaf during or after the event then it likely means that you had way too much noise. The worst thing you can do is not take action before tinnitus damage sets in.

Damage continues LONG after initial exposure to cochlear neurons - http://www.jneurosci.org/content/29/45/14077

Once the damage has been done there's no way to fix it and you'll likely have it the rest of your life. If you have tinnitus already then there's nothing you can other than to mitigate the problem. Taking vitamins may only help stop it from getting worse.

However for OTC medications this is what I would do. I take all of these together at the maximum UL dosage or just slightly above after a noise event for at least 2 weeks. Take full dose the first time and then half dose every 12 hours for maximum effect instead of full dose once a day.

What to do:
What ever you do don't listen to any loud noises 90db+ for at least a month if not a year.
Exercise to increase circulation in ear. There's little circulation in the ear so this is important.
Take carbohydrates (such as juice) or with a meal with these vitamins.
Try and avoid salt.
Get medical help.

What to take daily (divide numbers by 2 for half day dose.):
Vitamin A - 16,000 IU
Vitamin C - 1,750mg
Vitamin E - 1,600 IU
Magnesium - 1,000mg
L-Carnitine - 1,000mg
NAC - 1,200mg (N-Acetyl-L-Cysteine) - 1,800mg first day
A-Lipoic Acid - 600mg
Calcium - 100% DV
Vitamin D - 100% DV

Studies/articles showing possible benefits:
Vitamin A, C, E, & Magnesium - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1950331/
A-Lipoic Acid - https://www.ncbi.nlm.nih.gov/pubmed/25751698/
NAC - https://www.ncbi.nlm.nih.gov/pubmed/25763866 (It was tried with a massive dose but I would expect it to do nothing if the surgery itself doesn't cause trauma/free radicals which cause damage.)
L-Carnitine - https://www.ncbi.nlm.nih.gov/pubmed/21718695
Calcium - Helps repair inner ear bones
Vitamin D - Helps calcium absorption

Disclaimer: I'm not a doctor and I don't give professional medical advice.