If you drink and drive, things can quickly get expensive. In most cases, you will have to pay procedural costs along with fees for the bureaucracy and analyses.
On top of that, you face the following penalties:
From 0.05 to 0.079% blood alcohol: A formal reprimand and a fine of around CHF 600-800. If you have also broken another traffic regulation (for example, if you were speeding), you will disqualified from driving for at least one month and face a heavy fine; the exact amount depends on your financial circumstances.
Over 0.08%: Disqualification from driving for at least three months and a heavy fine; the exact amount depends on your financial circumstances and how much you are over the limit. In addition, you will receive a suspended monetary penalty. In case of a repeat offence, you also face a prison sentence of one to three years.
Over 0.16%: In addition, a compulsory driving aptitude test: A specialist will determine whether you have an alcohol addiction. You will have to remain abstinent for several months and provide proof that you have done so (by means of a hair sample). You will only get your driving licence back if the specialist gives you the green light.
How quickly you reach the drink-driving limit depends on various factors, in particular, what you drink, how fast you drink it and how big you are. It is difficult to say exactly how much alcohol will take you over the limit. You should therefore be wary of advice offered on this question.
It is best to abstain from alcohol altogether if you have to drive. Even just one glass of beer or wine can affect your vision and reactions and can lead you to take more risks.