Here is the safety profile for Piracetam:

Toxicity and harm potential

Adverse effects, although rare and of short duration are limited to anxiety, insomnia, drowsiness, headaches and agitation. It may be safe for up to 18 months in humans at doses of 3.2g daily with one year-long study in ambulatory patients with Alzheimer's using 8g daily reporting no side effects.[10] However, a possibility for adverse drug-drug interactions persists for piracetam due to it interacting with blood in an anti-clotting manner (and such, caution should be taken when pairing piracetam with pharmaceutical blood thinning agents such as Warfarin or potent nutraceutical options).

No fatal overdoses associated with piracetam use have been reported as of 2016. In animal models (rodents, dogs, and marmoset), an LD50 failed to be established at the dosage of 8-10g/kg.

Regardless, it is strongly recommended that one use harm reduction practices when using this substance.
Lethal dosage

The median lethal dosage (LD50) of piracetam has not been officially published as it has low abuse potential, but the typical dosage is two grams once to three times a day.
Dependence and abuse potential

The chronic use of piracetam can be considered as not addictive with a low potential for abuse. It does not seem to be capable of causing psychological dependence among certain users.

Tolerance to many of the effects of piracetam develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). Piracetam may presents cross-tolerance with all racetam nootropics, meaning that after the consumption of piracetam certain nootropicss such as aniracetam and pramiracetam may have a reduced effect.
Dangerous interactions

Piracetam showed nonselective MAO activity in a rat study.[11][12] Piracetam and MAOIs are a potentially dangerous combination. It is likely that MAOIs could increase the effects of piracetam unpredictably. Taking this chemical while on prescription MAOIs is strongly discouraged.

As you can see, with the exception of MAOI's it is exceptionally safe.

I have been using it to treat tinnitus and restore lost high frequency
hearing (in my case hearing went from upper limit of 8Khz back to 17Khz) with
100% success for more than ten years.

Now, because the FDA is blocking imports, I can't get it.

I would like to encourage everyone to write the FDA and their congress critters to put a stop to this. With such a good safety profile there is absolutely NO justification for this and a lot of people, myself included, will needlessly suffer.