Using diphenhydramine(50mg pill) for sleep i have a high tolerance, i'm a 22 yr old female 111lbs. would 100mg be ok since 50mg doesn't work?

No: Regardless of your tolerance, 100 mg of Benadryl (diphenhydramine) is not a safe or studied dose. You can still experience slowing of reflexes and thought processes even if you do not feel sleepy with Benadryl (diphenhydramine). You should see a sleep specialist to help you with your insomnia.

Not advised: you're already maxed-up for this indication, insomnia, and diphenhydramine should only be used on the short term, please visit your doctor to help you out in that matter, good luck

Insomnia: Use of sleeping medications is not a good idea except in very short time and medications like Ambien (zolpidem) or Melatonin are first line. Sleep hygiene works well for most people. Go to bed same time daily, Sleep in dark rooms, avoid external stimulants, exercise, healthy diet, avoid daytime naps or laying in bed, get from bed if not sleepy