I was prescribed 25mg tablets (one at bedtime) of Amitriptyline after my concussion as a sleep aid and to prevent headaches. It definitely knocked me out about 2 hours after taking one and seemed to help with the headaches over time. I took it daily for about a week but started getting unwanted side effects including sleepy during the day, a feeling of too much adrenaline (excess norepinephrine I would suspect) and muscle twitches and hand tremors. I discontinued use after that. I can see how it could be beneficial for some people but it really depends on the person's brain chemistry at the time of dosing induction. It has many different mechanisms of actions resulting in many side effects, some may be helpful, some may cause issues.

Also, it should be noted that amitriptyline is a tri-cyclic antidepressant that affects serotonin levels and SHOULD NOT be taken with any other serotonergic agents; Don't take amitriptyline with anti-depressant meds like SSRI, MAOI, drugs such as adderall, ritalin, or any stimulants, DXM (found in cough syrup), and definitely not with supplements like L-Tryptophan or 5-HTP. Mixing these substances can result in a life-threatening medical condition known as serotonin syndrome. This information is freely available on the internet and if you take any of these medications it would be wise to use the medication checker sticky located at the top of this forum. I have heard of some physicians mixing drugs in very irresponsible ways and in the end you should be the one who makes sure there are no interactions between medications.