Proquin XR tablets should be taken whole and never split, crushed, or chewed. Proquin XR should be taken with the main meal of the day. Proquin XR should be administered at least 4 hours before, or 2 hours after, antacids containing magnesium or aluminum, sucralfate, VIDEX^® (didanosine), chewable/buffed tablets or pediatric powder, metal cations such as iron, and multivitamin preparations containing zinc. Proquin XR is not interchangeable with other ciprofloxacin extended-release (Cipro^® XR) or immediate-release (Cipro^®) oral formulations. Proquin XR is contraindicated in persons with a history of hypersensitivity to ciprofloxacin or any member of the quinolone class of antimicrobial agents, or any of the product components. The incidence of all adverse events (regardless of relationship to study drug) reported for at least 2% of patients treated with Proquin XR during the entire 5-week study period was as follows: fungal infection (2.6%), nasopharyngitis (2.6%), headache (2.4%), and micturition urgency (2.0%). The safety and effectiveness of Proquin XR in pediatric patients and adolescents (less than 18 years of age), pregnant women, and lactating women have not been established. Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported in patients receiving quinolone therapy. Serious and fatal reactions have been reported in patients receiving concurrent administration of fluoroquinolones, including ciprofloxacin, and theophylline.