Dexmethylphenidate (Focalin) is a mild CNS stimulant that acts by blocking the reuptake of norepinephrine and dopamine in the brain. It is indicated in the treatment of patients with ADHD (Attention-deficit hyperactivity disorder).

Dexmethylphenidate Uses:

• ADHD:
  • Treatment of ADHD

Dexmethylphenidate (Focalin) Dose in Adults

Dexmethylphenidate (Focalin) Dose in the treatment of Attention-deficit/ hyperactivity disorder (ADHD):

• Patients not currently taking methylphenidate or who are on other stimulants: Oral:
  • Immediate release:
    • Initial: 2.5 mg two times per day;
    • The dosage can be changed in weekly intervals in increments of 2.5 to 5 mg (the daily maximum dose is 20 mg).
  • Extended-release:
    • Initial: 10 mg one time per day;
    • The dosage can be changed in 10 mg weekly increments (40 mg/day is the maximum).

Conversion to dexmethylphenidate from methylphenidate:

• Immediate release and extended-release:
  • Initial: One-half the total daily dose of racemic methylphenidate

Conversion from dexmethylphenidate immediate-release to dexmethylphenidate extended-release:

• Patients currently using dexmethylphenidate immediate-release may be switched to the same daily dose of dexmethylphenidate extended-release.
• Dose reductions and discontinuation:
  • If there is an aggravation of symptoms discontinue therapy or adjust the dose.
  • If no improvement is observed in patient symptoms stop therapy.

Dexmethylphenidate (Focalin) Dose in Childrens

Dexmethylphenidate (Focalin) Dose in the treatment of Attention-deficit/ hyperactivity disorder (ADHD):

Note: Reduce dose or discontinue in patients with paradoxical aggravation of symptoms or other adverse events. Discontinue if no improvement is seen after appropriate dosage adjustment over a 1-month period of time.

• Children ≥6 years and Adolescents: Oral:
  • Patients not currently taking methylphenidate:
    • Immediate-release:
      • Initial: 2.5 mg two times per day;
      • Doses should be taken at least 4 hours apart;
      • The dosage can be changed every week in increments of 2.5 to 5 mg.
      • The maximum daily dose is 20 mg; however, with careful supervision, some individuals may need and be able to take doses as high as 50 mg daily.
    • Extended-release:
      • Initial: 5 mg once per day;
      • The dosage may be adjusted in increments of 5 mg/day at weekly intervals;
      • The maximum daily dose is 30 mg/day; however, some patients may require and tolerate daily doses up to 50 mg/day with frequent monitoring.
  • Conversion to dexmethylphenidate from methylphenidate:
    • Immediate-release:
      • Initial: Half the total daily dose of racemic methylphenidate;
      • The maximum daily dexmethylphenidate dose is 20 mg/day; however, some patients may require and tolerate daily doses up to 50 mg/day with frequent monitoring.
    • Extended-release:
      • Initial: Half the total daily dose of racemic methylphenidate;
      • The maximum daily dexmethylphenidate dose is 30 mg/day; however, some patients may require and tolerate daily doses up to 50 mg/day with frequent monitoring.
  • Conversion from dexmethylphenidate immediate-release to dexmethylphenidate extended-release:
    • When changing from Focalin tablets to Focalin XR capsules, switch to the same daily dose using Focalin XR;
    • The maximum daily dose is 30 mg/day; however, some patients may require and tolerate daily doses up to 50 mg per day with regular monitoring.

Pregnancy Risk Factor C

• Studies on animal reproduction have demonstrated that negative outcomes are possible.
• Dexmethylphenidate, the active d-three enantiomer racemic methylphenidate, is available. Refer to Methylphenidate monograph.

Use of dexmethylphenidate while breastfeeding

• If dexmethylphenidate can be eliminated from breast milk is unknown.
• Dexmethylphenidate however, is the active d-threoenantiomer racemic methylphenidate. Consequently, methylphenidate can be excreted into breastmilk.
• Dexmethylphenidate should not be given to nursing mothers unless it is prescribed by the manufacturer. For more information, refer to Methylphenidate monograph

Dexmethylphenidate (Focalin) Dose in Kidney Disease:

There dosage adjustment has not been studied. However, considering the extensive metabolism of inactive compounds, renal insufficiency expected to have minimal effect on the kinetics of dexmethylphenidate.   

Dexmethylphenidate (Focalin) Dose in Liver disease:

There are no dosage adjustments provided in the manufacturer's labeling (it has not been studied).     

Adverse Reactions The actual frequency may depend on the formulation and/or the dose. For negative effects associated with other methylphenidate compounds, see Methylphenidate as well.

Common Side Effects of Dexmethylphenidate (Focalin):

• Central Nervous System:
  • Headache
  • Insomnia
  • Jitteriness
  • Anxiety
• Gastrointestinal:
  • Decreased Appetite
  • Xerostomia
  • Abdominal Pain

Less Common Side Effects Of Dexmethylphenidate (Focalin):

• Central Nervous System:
  • Dizziness
  • Irritability
  • Depression
  • Emotional Lability
• Dermatologic:
  • Pruritus
• Gastrointestinal:
  • Nausea
  • Dyspepsia
  • Vomiting
  • Anorexia
• Respiratory:
  • Pharyngolaryngeal Pain
  • Nasal Congestion
• Miscellaneous:
  • Fever

Frequency of side effects not defined:

• Central Nervous System:
  • Drug Abuse
  • Drug Dependence
• Endocrine & Metabolic:
  • Growth Suppression
  • Weight Loss

Contraindications to Dexmethylphenidate (Focalin):

if the patient is allergic to methylphenidate, any formulation ingredient, or if they are using another medication within 14 days after stopping an MAOI.

Warnings and precautions

• Cardiovascular events
  • Treatment with CNS stimulant has been linked to sudden death in children and teens with preexisting structural heart abnormalities. Adults have also experienced sudden death, stroke and myocardial injury.
  • A large retrospective cohort study that included 1,200,438 children and adolescents (aged 2-24 years) who were prescribed methylphenidate or dexmethylphenidate, as well as dextroamphetamines or amphetamine salts or pemoline, found no evidence of ADHD medication use increasing the risk of sudden cardiac death, acute coronary infarction or stroke.
  • Stimulants should be avoided by patients with established structural heart problems, cardiomyopathy, or severe heart rhythm abnormalities.
  • Patients with angina, severe hypertension, heart failure, arrhythmias or recent myocardial injury may be contraindicated to some products.
  • Assess your medical history and family history for sudden death or ventricular arrhythmia. Next, start therapy and conduct a physical exam. If you find that there is evidence of cardiac disease, then do another evaluation, such as an ECG or echocardiogram.
  • Patients who experience exertional chest pain, unexplained systolic symptoms, or other signs of cardiac disease should be evaluated immediately.
• Hypersensitivity reactions
  • Patients treated with methylphenidate have experienced hypersensitivity reactions, including angioedema, and anaphylactic reactions.
• Peripheral vasculopathy
  • Stimulants can cause peripheral vasculopathy including Raynaud phenomenon. Usually, there are mild, intermittent symptoms that subside with dose reductions or discontinuation.
  • The effects of peripheral vasculopathy on the periphery have been documented at various times and at therapeutic doses in all ages.
  • Soft tissue and digital ulceration are less common. Monitor for any changes in therapy and seek additional evaluation (e.g. If necessary, a rheumatologist will evaluate the situation.
• Priapism
  • According to the labeling of the manufacturers and the FDA warning, there have been at least 22 cases where patients who used atomoxetine and methylphenidate had persistent (>4-hour) and painful erections.
  • Prapism can be caused by therapy, which may occur after an increase in dosage or during withdrawal (drug holidays) or discontinuation.
  • Patients who have certain hematological disorders (eg, sickle cells disease), malignancies or perineal trauma may be at higher risk.
  • Patients with priapism should stop taking medication and get immediate medical attention.
  • For severe cases, seek urgent urological consultation.
  • Avoidance of stimulants and atomoxetine is possible in severe cases of priapism.
• Visual disturbance
  • Patients with impaired vision due to stimulants can experience difficulty in accommodation.
• Abuse and dependence: [US Boxed Warning]
  • There is a high risk of abuse and dependence with CNS stimulants such as dexmethylphenidate and methylphenidate products and amphetamines.
  • Before prescribing therapy, assess the risk of abuse. Close monitoring of signs of abuse and dependence during treatment is necessary.
• Cardiovascular diseases
  • CNS stimulants can increase heart rate (mean rise 3 to 6 bpm) or blood pressure (mean rise 2 to 4 mg Hg).
  • Patients with hypertension, heart disease, recent myocardial injury, ventricular arrhythmia and other cardiovascular conditions should be cautious.
• Psychiatric disorders
  • Patients with suspected psychosis (may worsen symptoms of behavior disorder and thought disorder) or bipolar disorder should be careful.
  • Stimulant use can cause new-onset psychosis and mania.
  • Before starting treatment, patients should be tested for bipolar disorder.
  • Possible association with aggressive behavior in children or hostility (causal relationship unknown); monitor for the development of behavioral disorders.
  • ADHD patients are more likely to attempt suicide. However, large cohort studies have not shown a causal relationship between methylphenidate use and suicidal thoughts or attempts.
  • Suicide-related behavior should be monitored closely.
• Seizure disorder
  • There is limited information available about stimulant use in seizure disorder.
  • Patients with ADHD have a higher risk of seizure activity than the general population. However, a retrospective analysis using data from drug claims showed that patients who used stimulant medication had a lower risk.
  • If seizures occur, discontinue therapy
• Tourette syndrome/tics
  • Patients with Tourette syndrome and other tic disorders should be cautious.
  • Although stimulants can cause tics (motor-phonic and Tourette syndrome), evidence of an increase in tics is not available.
  • Assess for tics

Dexmethylphenidate: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring parameters:

• Hypertensive patients may have high blood pressure and high heart rates.
• CBC with differential platelet and platelet counts
• Signs of peripheral vasculopathy (eg digital changes)
• Children's height and weight;
• Signs of abuse, misuse, or addiction
• Regularly assess patients to determine if the medication should be continued or stopped.

If ADHD treatment is being used, it is important to assess the cardiovascular risk. Before you start any medicine, such as an ECG, monitor your heart rate and blood pressure.

How to administer Dexmethylphenidate (Focalin)?

Extended-release:

• Administer the capsules once a day in the morning with or without food;
• Do not crush, chew, or divide. Capsules may be opened and contents sprinkled over a spoonful of applesauce; consume immediately and swallow without chewing;
• Do not store for future use.

Immediate-release:

• Take two times per day at least 4 hours apart; may be taken with or without food.

Mechanism of action of Dexmethylphenidate (Focalin):

• Dexmethylphenidate, also known as d-threoenantiomer or racemic methylphenidate, is the active form of racemic methylphenidate. 
• It acts as a CNS stimulant. It blocks the reuptake and release of dopamine and norepinephrine, and increases their availability into the extraneuronal spaces.

The onset of action:

• Rapid, within 1 to 2 hours of an effective dose

Duration of action:

• Immediate-release: 3 to 5 hours;
• extended-release: 9 to 12 hours.

Absorption:

• Immediate-release: Rapid;
• Extended-release: Bimodal (with 2 peak concentrations ~4 hours apart)

Protein binding:

• Unknown; racemic methylphenidate: 12% to 15%

Metabolism:

• Via de-esterification to an inactive metabolite, d-α-phenyl-piperidine acetate (d-ritalinic acid)

Bioavailability:

• 22% to 25%

Half-life elimination:

Immediate-release:

• Children: 2 to 3 hours
• Adults: 3 hours

Time to peak: Fasting:

• Immediate-release: 1 to 1.5 hours; after a high-fat meal: 2.9 hours
• Extended-release: First peak: 1.5 hours (range: 1 to 4 hours); Second peak: 6.5 hours (range: 4.5 to 7 hours)

Excretion:

• Urine (90%, primarily as inactive metabolite)   

International Brand Names of Dexmethylphenidate:

• Focalin
• Focalin XR
• Neoaradix

Dexmethylphenidate Brand Names in Pakistan:

In Pakistan No Brands are Available.