What are the indications for Medilisk?

Cycloserine (Medilisk) Indications and Uses

Cycloserine (Medilisk) is primarily indicated for the treatment of drug-resistant tuberculosis in patients with organisms that have known or presumed susceptibility to the agent. 1, 2

Primary Indications

• Second-line treatment for drug-resistant tuberculosis
• Temporary treatment for tuberculosis patients with acute hepatitis (in combination with other non-hepatotoxic drugs) 1

Dosing Guidelines

Adults

• 10-15 mg/kg per day (maximum 1,000 mg)
• Usually administered as 500-750 mg/day in two divided doses
• Lower doses (500 mg/day) are associated with fewer adverse effects 2
• Serum concentration monitoring recommended (target peak: 20-35 mg/ml) 1, 2

Children

• 10-15 mg/kg per day (maximum 1.0 g/day) 1

Special Populations

Renal Impairment

• Not recommended for patients with creatinine clearance <50 ml/minute unless on hemodialysis 1, 2
• For hemodialysis patients: 500 mg three times weekly or 250 mg daily 1, 2
• Serum drug concentration monitoring essential 2

Hepatic Disease

• No specific precautions except in patients with alcohol-related hepatitis who have increased seizure risk 1, 2

Pregnancy

• Use only when no suitable alternatives exist due to limited safety data 1, 2
• Crosses the placenta 1

Adverse Effects

Neuropsychiatric Effects (Most Common)

• Seizures (16% with 500 mg twice daily; 3% with 500 mg once daily) 1, 2
• Headache, restlessness, anxiety, depression, psychosis 2
• May exacerbate underlying seizure disorders or mental illness 1, 2
• Peripheral neuritis (rare) 1

Prevention of Neuropsychiatric Effects

• Pyridoxine supplementation (100-200 mg/day) recommended 1, 2
• Start with lower doses and titrate slowly 2
• Monthly neuropsychiatric status assessment 1, 2

Monitoring Requirements

• Baseline and monthly neuropsychiatric assessment 1, 2
• Serum drug concentration monitoring until appropriate dose established 1
• For patients taking phenytoin, monitor phenytoin serum concentrations 1, 2

Formulation

• Available as 250 mg capsules 1

Clinical Pearls

• Higher toxicity risk with doses exceeding 500 mg/day 1, 2
• CSF concentrations approach serum levels, making it useful for CNS tuberculosis 1
• Dose reduction or discontinuation necessary if severe neuropsychiatric symptoms develop 2
• Patient education about potential neuropsychiatric symptoms is essential 2

The use of cycloserine requires careful monitoring due to its significant neuropsychiatric side effect profile. The benefit of treating drug-resistant tuberculosis must be weighed against these potential adverse effects, with appropriate dose adjustments and monitoring to minimize risks.