Ciprofloxacin : Therapeutic uses, Dosage & Side Effects
Ciprofloxacin is the prototype Fluoroquinolones (FQ) & most potent first generation FQ, used to treat different types of bacterial infections.
Dose : 250-750 mg (Oral), 100-200 mg (IV)
Route : Oral, IV, Topical (Eye drops, Ear drops)
Onset of action : ?
Plasma Half-life : 3-5 hours
Duration of action : ?
Bioavailability : 60-80% (Oral)
Plasma protein binding : 20-35%
Metabolism : Liver
Pregnancy risk category : C
Chemical formula : C17H18FN3O3
IUPAC name : 1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-quinoline-3-carboxylic acid
Trade name : Cifran, Ciplox, Ciprobid, Quintor, Ciprolet, Cipro, Ciloxan, Neofloxin, Cipro XR, Proquin XR
Antibacterial spectrum :
Ciprofloxacin is active against a broad range of bacteria including both gram-negative & gram-positive bacteria, the most susceptible ones are the aerobic gram-negative bacilli, especially the Enterobacteriaceae and Neisseria.
Therapeutic uses : Ciprofloxacin is effective in a broad range of infections. Because of wide-spectrum bactericidal activity, oral efficacy and good tolerability, it is being extensively employed for blind therapy of any infection, but should not be used for minor cases or where gram-positive organisms and /or anaerobes are primarily causative. In severe infections, therapy may be initiated by i.v. infusion and then switched over to oral route.
Ciprofloxacin can be used for following purpose :
- Urinary tract infections : High cure rates, even in complicated cases or those with indwelling catheters/prostatitis, have been achieved. Chronic Pseudomonas infections respond less completely.
- Gonorrhoea : Initially a single 500 mg dose was nearly 100% curative in non-PPNG as well as PPNG infections, but cure rate has declined in the recent years due to emergence of resistance.
- Chancroid : 500 mg BD for 3 days is an excellent alternative to ceftriaxone/ erythromycin.
- Bacterial gastroenteritis : Severe cases due to EPEC, Shigella, Salmonella and Campy. Jejuni respond quickly. It has also been used to reduce stool volume in cholera.
- Typhoid : Ciprofloxacin is the first choice drug in typhoid fever since chloramphenicol, ampicillin and cotrimoxazole have become unreliable due to development of resistance. In India and elsewhere up to 95% S. typhi isolates are sensitive to ciprofloxacin. However, increasing number of nonresponsive cases are being reported. A dose of 500-750 mg BD for 10 days is recommended. Patients unable to take the drug orally may be treated with 200 mg. i.v. 12 hourly in the beginning. It can also be used to treat typhoid carriers (750 mg B D for 4-8 weeks).
- Bone, soft tissue, gynaecological and wound infections : caused by resistant Staph. and gram negative bacteria: high cure rates have been obtained but prolonged treatment with high doses is required in osteomyelitis and joint infection.
- Respiratory infections : Ciprofloxacin shoul not be used as the primary drug because pneumococci and streptococci have low and variable susceptibility. However, it can treat Mycoplasma Legionella, H. influenzae, Branh. catarrhalis and some streptococcal and pneumococcal infections besides gram-negative ones.
- Tuberculosis : It is now frequently used as a component of combination chemotherapy against multidrug resistant tuberculosis.
- Gram-negative septicaemias : Parenteral ciprofloxacin may be combined with 3rd generation cephalosporin or an aminoglycoside.
- Meningitis : Used in gram-negative bacterial meningitis, especially that occurring in immunocompromised patients or those with CSF shunts.
- Prophylaxis of infections in neutropenic / cancer and other susceptible patients.
- Conjunctivitis by gram-negative bacteria : topical therapy is effective
Mechanism of action : Fluoroquinolones enter bacteria through porin channels and exhibit antimicrobial effects on DNA gyrase (bacterial topoisomerase II) and bacterial topoisomerase IV.
- Inhibition of DNA gyrase results in relaxation of supercoiled DNA, promoting DNA strand breakage.
- Inhibition of topoisomerase IV impacts chromosomal stabilization during cell division, thus interfering with the separation of newly replicated DNA
Side effects : Ciprofloxacin has good safety record : side effects occur in ~10% patients, but are generally mild; withdrawal is needed only in 1 .5%. Following side effects may be seen :
- Gastrointestinal : nausea, vomiting, bad taste, anorexia. Because gut anaerobes are not affected- diarrhoea is infrequent.
- CNS : dizziness,headache, restlessness, anxiety, insomnia, impairment of concentration and dexterity (caution while driving), tremor. Seizures are rare, occur only at high doses or when predisposing factors are present : possibly reflect GABA antagonistic action of FQs.
- Skin/hypersensitivity: rash, pruritus, photosensitivity, urticaria, swelling of lips, etc. Serious cutaneous reactions are rare.
- Tendonitis and tendon rupture : a few cases have been reported.
- Articular cartilage erosion (arthropathy) has been observed in immature animals exposed to fluoroquinolones.
Drug Interactions :
- Plasma concentration of theophylline, caffeine and warfarin are increased by ciprofloxacin due to inhibition of metabolism : toxicity of these drugs can occur.
- NSAIDs may enhance the CNS toxicity of FQs; seizures are reported.
- Antacids, sucralfate and iron salts given concurrently reduce absorption of FQs.
Warning :
- Fluoroquinolones are associated with an increased risk of tendinitis and tendon rupture in all ages. This risk is further increased in older patients usually over 60 years of age, in patients taking corticosteroid drugs, and in patients with kidney, heart, or lung transplants.
- Fluoroquinolones may exacerbate muscle weakness in persons with myasthenia gravis.
Contraindications :
- Ciprofloxacin and other FQs are contraindicated during pregnancy.
- FQs should be used cautionly in children (under 18 years).
- Ciprofloxacin is contraindicated in persons with a history of hypersensitivity to ciprofloxacin, any member of the quinolone class of antibacterials, or any of the product components.
- Concomitant administration with tizanidine is contraindicated.
For detailed query or in case of uncertainty, Always consult your doctor or pharmacist.
