ciprofloxacin, Cipro, Cipro XR, Proquin XR (cont.)

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DOSING: For most infections the recommended oral dose for adults is 250-750 mg (immediate release tablets) every 12 hours or 500-1000 mg (extended release tablets) every 24 hours. The usual intravenous dose is 200-400 mg every 8-12 hours.

DRUG INTERACTIONS: Ciprofloxacin administered together with theophylline (Respbid, Slo-Bid, Theo-24, Theolair) can lead to elevated, toxic blood levels of theophylline. Theophylline is used to open airways in the treatment of asthma. Toxic levels of theophylline can lead to seizures, and disturbances in heart rhythm. If concurrent use of ciprofloxacin and theophylline cannot be avoided, frequent blood tests to monitor theophylline blood levels are recommended.

Ciprofloxacin increases the effect of tizanidine (Zanaflex) that is used to treat muscle spasticity. Therefore, the two drugs should not be combined.

Iron salts (for example, ferrous sulfate) may reduce the absorption of ciprofloxacin because of formation of a ciprofloxacin-iron complex that is not absorbable. Antacids also may reduce the absorption of ciprofloxacin. If patients are receiving iron salts or antacids and ciprofloxacin, the ciprofloxacin should be given two hours before or six hours after the iron salt or antacid.

Ciprofloxacin may increase the blood thinning effect of warfarin (Coumadin). The reason for this is unknown. Anticoagulant activity should be monitored after starting or stopping ciprofloxacin.

Sevelamer (Renagel) may reduce the absorption of ciprofloxacin and possibly reduce the effectiveness of ciprofloxacin. Milk and orange juice also may reduce the absorption of ciprofloxacin. Ciprofloxacin, as with iron and antacids, should be given two hours before or six hours after milk or orange juice.

Administration of ciprofloxacin with diabetic medications (for example glyburide [Micronase, Diabeta, Glynase, Prestab]) may lead to severe low blood glucose.

Ciprofloxacin may increase blood concentrations of sildenafil (Viagra) that is used for treating erectile dysfunction. This combination should be avoided if possible.

Medically Reviewed by a Doctor on 10/9/2013


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