What might Westley be suffering from if he displayed drowsiness and slurred speech before deputies entered?

If Westley is displaying drowsiness and slurred speech, it aligns with the effects commonly associated with depressant consumption. Depressants work by slowing down the central nervous system, which can lead to symptoms such as increased drowsiness, impaired motor coordination, and speech difficulties. Common substances in this category include alcohol, benzodiazepines, and opiates, all of which can lead to the observed signs of slurred speech and drowsiness.

While alcohol intoxication can also lead to similar symptoms, which might create confusion in this context, the broader category of depressants encompasses a wider range of substances that could produce these effects. Therefore, recognizing that the physiological impact of depressants consistently results in drowsiness and slurred speech makes this the most fitting choice in the scenario presented.