Ofloxacin

# Ofloxacin ## Overview - **Classification**: Fluoroquinolone antibiotic. - **Mechanism**: Inhibits bacterial DNA gyrase and topoisomerase IV, essential for bacterial DNA replication. ## Primary Indications 1. **Community-acquired pneumonia (CAP)** - Treatment of susceptible bacterial infections. 2. **Acute bacterial exacerbation of chronic bronchitis (ABECB)** - Treatment of susceptible bacterial infections. 3. **Urinary Tract Infections (UTI)** - Uncomplicated and complicated UTIs, cystitis. 4. **Prostatitis** - Treatment of chronic bacterial prostatitis. 5. **Skin and Skin Structure Infections** - Uncomplicated infections. 6. **Sexually Transmitted Infections** - Uncomplicated urethral and cervical gonorrhea, chlamydia. ## Adult Dosing ### Standard Dosing **Community-acquired Pneumonia, ABECB, Uncomplicated Skin/Skin Structure Infections** - **Dose**: **400 mg** - **Frequency**: Every 12 hours (q12h) - **Route**: Oral (PO) or Intravenous (IV) - **Duration**: 10 days **Uncomplicated Cystitis** - **Dose**: **200 mg** - **Frequency**: q12h - **Route**: PO or IV - **Duration**: 3-7 days **Complicated UTI, Chronic Bacterial Prostatitis** - **Dose**: **300-400 mg** - **Frequency**: q12h - **Route**: PO or IV - **Duration**: 10 days (complicated UTI), 28 days (prostatitis) **Uncomplicated Urethral/Cervical Gonorrhea** - **Dose**: **400 mg** - **Frequency**: Single dose - **Route**: PO **Chlamydia (Urethral/Cervical)** - **Dose**: **300 mg** - **Frequency**: q12h - **Route**: PO - **Duration**: 7 days ### Dose Adjustments - **Renal Impairment**: Requires dose adjustment. - CrCl 20-50 mL/min: Administer usual dose q24h or 50% of usual dose q12h. - CrCl <20 mL/min: Administer 50% of usual dose q24h. - **Hepatic Impairment**: No specific dose adjustment generally recommended. Monitor carefully. - **Elderly Patients**: Monitor renal function; increased risk of QTc prolongation and tendon adverse effects. ## Pediatric Dosing **Note**: Systemic ofloxacin is **not routinely recommended** in pediatric patients <18 years due to potential for irreversible arthropathy in weight-bearing joints. Use only for severe infections where benefits clearly outweigh risks and alternative therapies are unsuitable (e.g., multidrug-resistant infections, anthrax exposure). Topical formulations (otic/ophthalmic) are commonly used. ### Neonates (0-28 days) - **Dose**: Generally **avoided** for systemic use. - **Special Notes**: Not recommended due to lack of safety data and arthropathy risk. ### Infants (1-12 months) - **Dose**: Generally **avoided** for systemic use. - **Special Notes**: Not recommended due to arthropathy risk. ### Children (1-12 years) - **Dose**: **15 mg/kg/day** - **Frequency**: Divided q12h - **Maximum**: **400 mg/dose**; **800 mg/day** - **Special Notes**: Use only for specific, severe infections (e.g., MDR-TB, anthrax prophylaxis, severe *Pseudomonas* infections where other options fail). **Monitor closely for joint pain/swelling.** ### Adolescents (13-18 years) - **Dose**: **15 mg/kg/day** (up to adult dose) - **Frequency**: Divided q12h - **Maximum**: **400 mg/dose**; **800 mg/day** - **Special Notes**: Same considerations as children regarding arthropathy risk. Use only if benefits outweigh risks. ## Safety Information ### Contraindications - **Absolute**: Hypersensitivity to ofloxacin or other fluoroquinolones. - **Absolute**: History of tendon disorders related to fluoroquinolone use. - **Absolute**: Myasthenia gravis (risk of exacerbating muscle weakness). - **Absolute**: Children <18 years (for systemic use, generally avoided unless benefits outweigh risks in specific severe cases). ### Common Adverse Effects - **Common (1-10%)**: Nausea, diarrhea, headache, dizziness, insomnia. - **Serious but Rare**: Tendinitis/tendon rupture (Achilles), peripheral neuropathy, QTc prolongation/arrhythmias, *Clostridioides difficile*-associated diarrhea (CDAD), seizures, dysglycemia (hypo- or hyperglycemia), psychiatric reactions (e.g., depression, hallucinations), aortic aneurysm/dissection. ### Key Drug Interactions - **Antacids (Mg, Al, Ca), Sucralfate, Iron, Zinc**: Decreased ofloxacin absorption. Separate administration by at least **2-4 hours**. - **Warfarin**: Enhanced anticoagulant effect. Monitor **INR** closely. - **QTc prolonging drugs (e.g., Class IA/III antiarrhythmics, TCAs)**: Increased risk of QTc prolongation. Avoid co-administration if possible. - **Corticosteroids**: Increased risk of tendon rupture, especially in elderly. Avoid concurrent use if possible. - **Theophylline**: Increased theophylline levels and toxicity. Monitor **theophylline levels**. - **NSAIDs**: Increased risk of CNS stimulation and seizures. Use with caution. - **Oral Hypoglycemics/Insulin**: Risk of dysglycemia (hypo- or hyperglycemia). Monitor **blood glucose** closely. ## Monitoring & Follow-up - **Before Treatment**: Renal function (CrCl). Consider baseline ECG if cardiac risk factors or concurrent QTc-prolonging drugs. - **During Treatment**: Monitor renal function in patients with impairment. Monitor **blood glucose** in diabetic patients. Monitor **INR** if on warfarin. - **Clinical Signs**: Watch for new-onset tendon pain/swelling, muscle weakness, severe diarrhea, numbness/tingling, signs of arrhythmia (palpitations, syncope), mood changes. ## Clinical Pearls - 💡 **Black Box Warning**: Fluoroquinolones carry a boxed warning for serious adverse reactions including tendinitis/tendon rupture, peripheral neuropathy, CNS effects, and worsening of myasthenia gravis. - 💡 **Administration Timing**: To ensure adequate absorption, take ofloxacin at least **2 hours before or 4 hours after** magnesium/aluminum-containing antacids, sucralfate, iron, or zinc. - 💡 **Hydration**: Maintain adequate hydration during therapy to prevent crystalluria. - 💡 **Photosensitivity**: Advise patients to avoid excessive sun exposure or use protective clothing/sunscreen due to photosensitivity risk. - 💡 **Pediatric Systemic Use**: Generally **avoided in children <18 years** due to arthropathy risk unless benefits clearly outweigh risks for severe, life-threatening infections. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.