moxifloxacin hydrochloride: clinical use

Prescribing considerations

• Systemic fluoroquinolones should be used only when commonly recommended antibiotics are inappropriate.
• Assess previous serious quinolone reactions, cardiac and vascular risk, tendon risk, neurological or psychiatric disease, seizure susceptibility, myasthenia gravis, dysglycaemia risk and hepatic function.
• Do not use oral monotherapy for pelvic inflammatory disease unless moxifloxacin-resistant Neisseria gonorrhoeae has been excluded.

Contraindications and cautions

• Both selected products: hypersensitivity to moxifloxacin, another quinolone or a listed excipient.
• Tablets: pregnancy, breastfeeding, age under 18 years, previous quinolone-associated tendon disorder, specified QT-prolonging or pro-arrhythmic conditions, concurrent QT-prolonging medicines, severe hepatic impairment or marked transaminase elevation.
• Tablets contain lactose and are unsuitable for specified rare hereditary disorders of galactose metabolism or absorption.

Monitoring

• Discontinue systemic treatment at the first sign of a serious musculoskeletal, neurological, psychiatric, sensory, allergic, hepatic or severe skin reaction.
• Assess electrolytes and interacting medicines when clinically indicated.
• Monitor blood glucose carefully in patients with diabetes, particularly older people using insulin or a sulfonylurea.
• Consider more frequent INR monitoring with oral anticoagulants.
• Reassess ocular diagnosis and treatment if conjunctivitis does not improve as expected or deteriorates.

Clinical pharmacology

Moxifloxacin is a bactericidal fluoroquinolone that inhibits DNA gyrase and topoisomerase IV. Oral exposure is systemic and can prolong the QT interval; ocular administration produces low systemic concentrations.

Formulation and product differences

• The film-coated tablet is systemic, licensed only for adults and contains lactose.
• The eye-drop solution acts locally in bacterial conjunctivitis and has low systemic exposure.
• Eye drops are for ocular use only and must not be injected or introduced directly into the anterior chamber.

Eye drops

Route: Ophthalmic

Strengths: 0.5% w/v

Tablet

Route: Oral

Strengths: 400 mg