Ciprofloxacin toxicity

Theophylline Ciprofloxacin, fluvoxamine, etc. CYP1A2 Theophylline toxicity... 

L E. Quinidine. These are the classic signs of cinchon-ism and are adverse effects of quinidine and quinine, constituents of the cinchona tree. Some of these effects could be seen as toxic effects of phenytoin. However, auditory acuity is associated with cinchonism and not with phenytoin toxicity. Nausea but not the other effects could be associated with ciprofloxacin. Excessive drowsiness would be expected if diazepam were involved. These effects would not be expected with the estrogen replacement therapy. 

All quinolones interact with multivalent cations, forming chelation complexes resulting in reduced absorption. Major offenders are antacids vitamins containing calcium and iron can also be problematic. All fluoroquinolones interact with warfarin, didanosine (ddi), and phenytoin, resulting in decreased absorption or metabolism. Ciprofloxacin and other second-generation drugs interact with theophylline by decreasing its clearance, which leads to theophylline toxicity. 

About a week later, the patient was admitted to the hospital with acute onset of confusion and possible seizurelike activity. His wife states that he is compliant with medications and even felt well after initiation of antibiotics. Possible ciprofloxacin-induced acute CNS toxicity or drug interaction was suspected, and all his medications were discontinued. Which of the following is the possible explanation for the patient s acute onset of CNS toxicity ... 

D) He has cumulative CNS toxicity of ciprofloxacin secondary to poor urinary and prostatic tissue penetration. 

Displacement of GABA from its receptors by ciprofloxacin results in increased levels of the neu-roexcitatory transmitter and acute CNS toxicity. The neuroexcitation can range from irritability, confusion, and agitation to seizures and toxic psychosis. Ciprofloxacin has no interaction with alcohol. A disulfiramlike reaction (flushing, nausea, vomiting, and profuse sweating) is associated with alcohol and metronidazole. Avoid alcohol and metronidazole coadministration. 

Antistaphylococcal penicillins Methicillin [meth i SILL in], naf-cillin [naf SILL in], oxacillin [ox a SILL in], cloxacillin [klox a SILL in], and dicloxacillin [dye klox a SILL in] are penicillinase-resistant penicillins. Their use is restricted to the treatment of infections caused by penicillinase-producing staphylococci. Because of its toxicity, methicillin is rarely used. Methicillin-resistarft strains of Staphylococcus aureus (MRSA), currently a serious source of nosocomial (hospital-acquired) infections, are usually susceptible to vancomycin, and rarely to ciprofloxacin or rifampin. 

ROPINIROLE CIPROFLOXACIN t ropinirole levels Inhibition of CYP1 A2-mediated metabolism Watch for early features of toxicity (nausea, drowsiness)... 

CLOZAPINE, OLANZAPINE CIPROFLOXACIN t clozapine levels and possibly t olanzapine levels Ciprofloxacin inhibits CYP1A2 clozapine is primarily metabolized by CYP1A2, while olanzapine is partly metabolized by it Watch for the early features of toxicity to these antipsychotics. A1 in dose of clozapine and olanzapine may be required... 

CIPROFLOXACIN SODIUM BICARBONATE 1 solubility of ciprofloxacin in the urine, leading to t risk of crystalluria and renal damage t urinary pH caused by sodium bicarbonate can result in 1 ciprofloxacin solubility in the urine If both drugs are used concomitantly, the patient should be well hydrated and be monitored for signs of renal toxicity... 

The quinolones are contraindicated in patients with a history of hypersensitivity to any drug in this family. Absorption of the fluoroquinolones is reduced by antacids, iron, and zinc salts, and thus they should not be taken concurrently. Oral ciprofloxacin and enoxacin inhibit the metabolism of theophylline, and toxicity can occur when these two drugs are administered concurrently. Oral administration of the fluoroquinolones can cause convulsions and should therefore be done with caution in patients with central nervous system disorders. These drugs are not recommended for systemic administration in children, adolescents younger than age 18 years, or pregnant women. Topical administration is contraindicated for use in patients younger than 1 year of age. 

Uses. The decision to use chloramphenicol for systemic infection is influenced by its rare but serious toxic effects (see below). Its role in meningitis and brain abscess has largely been superseded by broad-spectrum cephalosporins such as cefotaxime and ceftriaxone, but it is a second-line agent for these indications, and for haemophilus epiglottitis in children. Chloramphenicol may be used for salmonella infections (t) hoid fever, salmonella septicaemia) but ciprofloxacin is now preferred. Topical administration is effective for bacterial conjunctivitis. 

Shigella. Mild disease requires no specific antimicrobial therapy but toxic shigellosis with high fever should be treated with ciprofloxacin or amoxicillin by mouth. 

Alternative or reserve drugs are used where there are problems of drug intolerance and bacterial resistance. They are in this class because of either greater toxicity or of lesser efficacy and include ethionamide (gastrointestinal irritation, allergic reactions), capreomycin (nephrotoxic), and cycloserine (effective but neurotoxic). Quinolone antibiotics such as ciprofloxacin and the more recently introduced macrolides such as clarithromycin and azithromycin also have useful activity against mycobacteria. 

---