Legally, as in if you were breathalysed you would be ok but even one drink can distort your ability to drive....and as one drink usually leads to another it's best to abstain altogether.
I metabolize alcohol differently on different occasions. Sometimes one drink can give me a significant head buzz. It depends on how much and what I've eaten for the last few days, how hydrated I am, and what the weather is! So.....it could be the case for you as well.
I don't understand how it happens, but a cold beer in the hot summer sun can send me up dancing on top of picnic tables. : )
Most people can only “burn off” an average of about 0.016 grams percent of ethanol (drinking alcohol) per hour.<br />
Some hints: (1) Eat first, especially high protein foods; (2) Don’t drink alcoholic beverages that have carbonation mixed with them; (3) slow down the alcohol intake so that your body has adequate time to process the alcohol (110 pound female, one standard drink per hour); (4) wait at least 2 hours after the last drink to start driving, SO LONG AS you feel no “buzz” at all.<br />
With only one drink, if you will follow those suggestions, you should have no problems.