Safinamide (Xadago) is a selective monoamine oxidase type B (MAO-B) inhibitor. It was approved for marketing by the U.S. FDA in 2017 and is used as an adjunctive treatment for Parkinson's disease (PD). This medication must be used in combination with levodopa/carbidopa and is indicated for Parkinson's disease patients experiencing "off" periods.
Precautions for Safinamide (Xadago) Administration
Hepatic Impairment
Moderate hepatic impairment (Child-Pugh Class B): The maximum recommended dose is 50 mg per day.
Severe hepatic impairment (Child-Pugh Class C): Use is contraindicated.
Renal Impairment: No dose adjustment is required.
Elderly Patients: No dose adjustment is required.
Important Administration Instructions
The tablets must be swallowed whole; they should not be split, crushed, or chewed.
The medication can be taken with or without food.
If a dose is missed, skip the missed dose and take the next dose at the regularly scheduled time the following day.
When discontinuing the medication, the dose should be tapered gradually (reduce from 100 mg to 50 mg, maintain this dose for one week, then discontinue completely).
Absolute Contraindications
Concomitant use with other MAO inhibitors (e.g., linezolid).
Concomitant use with opioid medications (e.g., pethidine, tramadol).
Concomitant use with tricyclic/tetracyclic antidepressants or serotonin-norepinephrine reuptake inhibitor (SNRI) antidepressants.
Concomitant use with dextromethorphan.
A history of hypersensitivity to safinamide.
Severe hepatic impairment (Child-Pugh Class C).
High-Risk Drug Interactions
Serotonergic Drugs: May trigger serotonin syndrome (selective serotonin reuptake inhibitors (SSRIs) should be used with caution and under monitoring).
Sympathomimetic Drugs: May cause severe hypertension (avoid cold medications containing ephedrine).
BCRP Substrate Drugs: May increase the concentrations of drugs such as methotrexate and mitoxantrone.
Dopamine Antagonists: Antipsychotic medications may reduce the efficacy of safinamide.
Monitoring During Safinamide (Xadago) Treatment
Efficacy Monitoring
Changes in "on" time (periods of good symptom control without troublesome dyskinesia).
The degree of reduction in "off" time.
Improvements in motor scores on the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III).
Assessment Frequency
Evaluate the initial response 2 weeks after starting treatment.
Monitor closely for 1-2 weeks after dose adjustment.
Conduct regular assessments every 3-6 months during the stable treatment phase.
Routine Monitoring Items
Blood Pressure Monitoring: At baseline, and at 1, 2, and 4 weeks after starting treatment, then every 3 months thereafter.
Hepatic Function: At baseline and every 6 months (monitor alanine transaminase (ALT) and aspartate transaminase (AST)).
Mental Status: Assess for hallucinations, impulsive behaviors, etc., at each follow-up visit.
Ophthalmic Examinations: For patients with risk factors for retinopathy, conduct ophthalmic examinations every 6-12 months.
