How long does amantadine stay in your blood?

It is possible. People using Amantadine should be cautioned not to drive as it can affect motor function. If they were driving erratically and were pulled over and seemed under the influence of a drug, you can be sited with dui. It doesnt have to just be alcohol. If you are impaired by anything, even an antihistamine, and you are pulled over and appear impaired, you can be sited with dui.

CNS Effects

Patients with a history of epilepsy or other "seizures" should be observed closely for possible increased seizure activity.

Patients receiving Amantadine Hydrochloride Tablets who note central nervous system effects or blurring of vision should be cautioned against driving or working in situations where alertness and adequate motor coordination are important.

That shouldn't cause a blood alcohol reading. Nor should it show on a drug screen. The half life is 17 hrs so it would be in the body for about 3.5 days.