OFLOREL 200/500MG TABLET

Indications

• Bacterial conjunctivitis
• Urinary tract infections
• Respiratory tract infections
• Skin and soft tissue infections
• Intra-abdominal infections

Dosage

Children: Refer to BNF for Children for appropriate dosing information, as pediatric doses vary based on the specific condition being treated.

Adults: Refer to BNF for specific indications and regimens, typically ranging from 200 mg to 800 mg daily, divided into one or two doses.

Mechanism of action

Ofloxacin exerts its antibacterial effect by inhibiting bacterial DNA gyrase and topoisomerase IV, enzymes critical for DNA replication and transcription. This action leads to the disruption of DNA supercoiling and ultimately results in cell death.

Pharmacodynamics

Ofloxacin exhibits concentration-dependent activity, meaning that higher drug concentrations correlate with greater antibacterial effects. The drug demonstrates time-dependent bactericidal activity, effectively killing bacteria as its concentration exceeds the minimum inhibitory concentration (MIC) for the organism. Its broad spectrum covers a wide range of pathogens, including both aerobic and anaerobic bacteria.

Pharmacokinetics

Ofloxacin is rapidly absorbed after oral administration, with peak plasma concentrations achieved within 1 to 2 hours. It has a bioavailability of approximately 95%. The drug is widely distributed throughout body tissues and fluids, including the lungs, kidneys, and prostate. Ofloxacin is metabolized in the liver, with renal excretion as the primary route of elimination, accounting for approximately 80% of the drug. Its half-life ranges from 4 to 6 hours, allowing for twice-daily dosing in most cases.

Contra-indications

• Hypersensitivity to ofloxacin or other quinolones
• History of tendon disorders related to fluoroquinolone use
• Myasthenia gravis
• Concurrent use with tizanidine

Adverse effects

• Nausea
• Diarrhea
• Dizziness
• Headache
• Rash
• Tendon rupture
• QT interval prolongation
• Peripheral neuropathy

Interactions

• Antacids containing magnesium or aluminum, as they can reduce absorption
• Warfarin, which may enhance anticoagulant effect
• Theophylline, as ofloxacin may increase plasma levels
• Corticosteroids, which may increase the risk of tendon rupture

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of tendon pain or inflammation
• Assess for potential QT interval prolongation in patients with pre-existing heart conditions
• Consider alternative therapies for myasthenia gravis patients

Pregnancy

Ofloxacin should only be used in pregnancy if the potential benefit justifies the potential risk to the fetus. Safety in pregnancy has not been established.

Breast-feeding

Ofloxacin is excreted in breast milk. Caution should be exercised when administering to breastfeeding women.

Storage

Store in a cool, dry place below 25°C. Protect from light.

Formulations

• Tablets
• Eye drops
• Infusion solution

Indications

• Bacterial vaginosis
• Amoebiasis
• Giardiasis
• Trichomoniasis
• Infections caused by anaerobic bacteria

Dosage

Children: Dosing in children is determined based on weight and the specific indication. Refer to the BNF for Children for appropriate dosing guidelines.

Adults: The usual adult dose is 1.5 g orally once daily for 5 days for bacterial vaginosis or 1 g orally once daily for 3 days for amoebiasis. Refer to the BNF for specific indications and adjustments.

Mechanism of action

Ornidazole exerts its antimicrobial effects through the reduction of its nitro group by anaerobic bacteria and protozoa, resulting in the formation of reactive intermediates that interact with microbial DNA. This leads to the disruption of DNA synthesis and ultimately causes cell death. The drug's activity is primarily directed towards anaerobic organisms, including certain protozoa.

Pharmacodynamics

Ornidazole demonstrates a concentration-dependent bactericidal effect against susceptible organisms. Its activity is influenced by the reduction potential of the nitro group, which is crucial for its antimicrobial action. Ornidazole has a broad spectrum of activity, particularly against anaerobes and protozoa, and has been shown to be effective in both in vitro and in vivo models of infection.

Pharmacokinetics

Ornidazole is rapidly and completely absorbed following oral administration, achieving peak plasma concentrations within 1 to 3 hours. It is widely distributed throughout the body, including the central nervous system. The drug is metabolized mainly in the liver, with a half-life of approximately 8 to 10 hours. Excretion occurs primarily through the urine, with a small fraction eliminated unchanged.

Contra-indications

• Hypersensitivity to ornidazole or any of its components
• History of neurological disorders, particularly seizures

Adverse effects

• Nausea
• Vomiting
• Headache
• Dizziness
• Dry mouth
• Metallic taste
• Peripheral neuropathy

Interactions

• Alcohol: Concurrent use may lead to disulfiram-like reactions including flushing, tachycardia, and vomiting
• Anticoagulants: May enhance the effects of warfarin and other anticoagulants
• Other neurotoxic agents: Increased risk of neurological side effects

Precautions

• Use with caution in patients with a history of seizures
• Monitor liver function in patients with hepatic impairment
• Discontinue if neurological symptoms occur

Pregnancy

Ornidazole is not recommended during pregnancy unless the benefit outweighs the risk, particularly in the first trimester.

Breast-feeding

Ornidazole is excreted in breast milk, caution is advised when administering to nursing mothers.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Tablets: 500 mg
• Infusion: 100 mg/100 mL