On average, your body clears roughly one Spanish UBE (10g of pure alcohol) per hour, but this is only a rule of thumb — body weight, sex, metabolism, food, and general health all change the pace. As a guide, it can take around 2–3 hours to eliminate a 330ml tercio of beer, two cañas, two small glasses of wine, or two single measures of spirits, and considerably longer after a heavy evening of tapas and copas.
This is why the morning after catches so many drivers out in Spain: if you drank heavily into the small hours, you can still be over 0.5 g/L the next morning, even after a full night's sleep. Sleep, coffee, water, and a shower may make you feel more awake, but they do not lower your BAC. The safest approach is to wait until you are certain all the alcohol has gone and you feel completely sober — and to use our calculator to estimate when that will be.