Do not drink alcohol while taking Levofloxacin. The combination will cause effects like disorientation, nervousness, disturbances in attention, memory loss, and confusion.
Cephalexin will not result in serious adverse reactions when taken with alcohol. However, there are other reasons not to mix them. Alcohol can cause unpleasant side effects on its own, like nausea, vomiting, or headaches. These can also be side effects of antibiotics.