What effect do cocaine and alcohol have on pupil size when used together?

When cocaine and alcohol are used together, they produce an overlapping effect on pupil size. Cocaine, as a stimulant, typically leads to pupil dilation (mydriasis) due to its action on the sympathetic nervous system. Alcohol, on the other hand, generally has a depressant effect and can lead to varying levels of pupil constriction or dilation depending on the amount consumed.

In cases where these substances are used simultaneously, their opposing actions can result in a synergistic effect. The stimulation from cocaine may be coupled with the depressant effects of alcohol, leading to a situation where the usual responses to either drug are altered. This overlapping effect illustrates the complexity of interactions between substances; rather than simply dilating or constricting the pupils, the combination can lead to a variable response that does not strictly adhere to the individual effects of each substance. This nuanced interaction is why the overlapping effect is the most accurate description of the combined impact.