Medication can be regarded as any over-the-counter or prescribed drug used for therapeutic purposes. Any medication, no matter how common, can have direct effects or side effects that may impair an engineer’s performance in the workplace. The risk is that these effects can be amplified if an individual is particularly sensitive to the medication or one of its ingredients. Hence, an aircraft maintenance engineer should be particularly careful when taking a medicine for the first time, and should ask his doctor whether any prescribed drug will affect his work performance. It is also wise with any medication to take the first dose at least 24 hours before any duty to ensure that it does not have any adverse effects.