Drug Guide
Dexmethylphenidate Hydrochloride; Serdexmethylphenidate Chloride
Classification
Therapeutic: Central Nervous System Stimulant for ADHD
Pharmacological: D-amethylphenidate prodrug with sustained release
FDA Approved Indications
- Attention Deficit Hyperactivity Disorder (ADHD)
Mechanism of Action
Dexmethylphenidate and serdexmethylphenidate increase the levels of dopamine and norepinephrine in the brain by inhibiting their reuptake, leading to improved attention and focus.
Dosage and Administration
Adult: Typically, 26.1 mg once daily in the morning. Dose may be adjusted based on response and tolerability.
Pediatric: Not approved for children under 6 years. For children 6 and older, dose adjustments should be based on clinical response and tolerability as per prescribing information.
Geriatric: Limited data; use with caution, starting at lower doses.
Renal Impairment: Use caution; consider dose adjustment due to potential decreased clearance.
Hepatic Impairment: Use with caution; no specific dosage recommendation available.
Pharmacokinetics
Absorption: Rapid absorption after oral administration.
Distribution: Widely distributed; crosses the blood-brain barrier.
Metabolism: Primarily metabolized in the liver, involving oxidative pathways.
Excretion: Excreted mainly via urine, both as metabolites and unchanged drug.
Half Life: Dexmethylphenidate: approximately 3-4 hours; Serdexmethylphenidate: prolonged release, effective duration around 12 hours.
Contraindications
- Use in patients with hypersensitivity to methylphenidate or other stimulants.
- History of Tourette’s syndrome or motor tics.
Precautions
- Monitor for signs of psychological dependence, hypertension, and exacerbation of pre-existing psychoses. Use cautiously in patients with cardiovascular disease, hypertension, or anxiety disorders. Avoid use during or within 14 days of MAOI therapy.
Adverse Reactions - Common
- Insomnia (Frequent)
- Decreased appetite (Frequent)
- Dry mouth (Common)
- Anxiety (Uncommon)
Adverse Reactions - Serious
- Cardiovascular events (e.g., chest pain, hypertension) (Rare)
- Psychosis or new or worsening psychiatric symptoms (Rare)
- Circulatory problems including Raynaud's phenomenon (Rare)
Drug-Drug Interactions
- Monoamine oxidase inhibitors (MAOIs),
- Other CNS stimulants,
- Antihypertensive agents, which may have additive effects.
Drug-Food Interactions
- Avoid taking with caffeine or acidic foods that may alter absorption.
Drug-Herb Interactions
- Potential interactions with herbal stimulants such as ephedra.
Nursing Implications
Assessment: Monitor growth in children, blood pressure, heart rate, and behavioral changes.
Diagnoses:
- Risk for cardiovascular complications
- Impaired social interaction related to behavioral changes
Implementation: Administer in the morning to reduce insomnia; monitor for adverse effects.
Evaluation: Assess effectiveness in reducing ADHD symptoms and monitor for side effects.
Patient/Family Teaching
- Take medication exactly as prescribed.
- Report any chest pain, sudden headache, or behavioral changes.
- Avoid alcohol and other CNS depressants.
- Maintain regular follow-up visits for monitoring.
Special Considerations
Black Box Warnings:
- Potential for abuse and dependence.
- Sudden death and cardiovascular events in patients with pre-existing structural cardiac abnormalities or other serious heart problems.
Genetic Factors: Genetic variations may influence metabolism, affecting efficacy and risk of side effects.
Lab Test Interference: May cause false positives in screening tests for amphetamines.
Overdose Management
Signs/Symptoms: Severe agitation, hallucinations, tachycardia, hyperreflexia, seizures.
Treatment: Supportive care, benzodiazepines for agitation, activated charcoal if early, and measures to control cardiovascular symptoms.
Storage and Handling
Storage: Store at room temperature away from light and moisture.
Stability: Stable under recommended conditions until expiration date.