Drowsiness May Occur...

So I wasn't feeling so great yesterday, wasn't sure if it was allergies or a cold coming on (everyone seems to be getting sick). So after lunch I went to safeway and bought some allergy/cold medicine, and went back to work. I took one little tablet and started to feel a little better. Then as I am doing some of my chemist work, I start to feel really tired, almost on the verge of falling asleep standing. I managed to stay awake and focus, some cold water helped with that, but it was only later yesterday evening that I discovered the source of my drowsiness. It turns out that I neglected to note that the pill I took 'may' cause drowsiness. Good news is that I woke up this morning feeling a lot better, so I guess it was probably allergies. You know what, I learned something today... I should read directions :)