Drowsiness is not a common side effect of ibuprofen.
If the only symptom is feeling sleepy, there is generally no cause for concern. In most cases, the drowsiness may be linked to the condition that led to taking ibuprofen in the first place. However, if the sleepiness is very intense or begins to interfere with daily activities, it is important to seek medical evaluation.
Some rare side effects of ibuprofen include depression or mental confusion, which can sometimes be mistaken for drowsiness. In extremely rare cases, ibuprofen may cause aseptic meningitis, a condition that can lead to drowsiness along with other symptoms such as fever, seizures, or even coma. If these symptoms occur, urgent medical attention in the emergency room is necessary.