Two specific kinds of drinking behavior significantly contribute to the level of work-performance problems: drinking right before or during working hours (including drinking at lunch and at company functions), and heavy drinking the night before that causes hangovers during work the next day.
And it isn’t just alcoholics who can generate problems in the workplace. Research has shown that the majority of alcohol-related work-performance problems are associated with nondependent drinkers who may occasionally drink too much -- not exclusively by alcohol-dependent employees.
There is always a level of risk when using any drug including prescription or over-the-counter medications.
Drug reactions vary from person to person. If you are taking a drug for the first time, you won’t know how it will affect you. It’s important to follow your doctor’s advice when taking prescription drugs and discuss any side-effects and how this might impact your work.
The effects of prescription drugs such as benzodiazepines (e.g. Xanax®) can have an impact on your work and you should discuss these with your doctor. Long term use in particular may become problematic.
This information was taken from the National Counsel on Alcoholism and Drug Dependence