Zenzedi (Dextroamphetamine) Dosing and Monitoring Guidelines for ADHD

Starting Doses by Age Group

Children (6–12 years) – Begin with 2.5 mg taken once daily in the morning after breakfast; a second 2.5 mg dose may be added around noon if needed. Single doses should not exceed 10 mg in children weighing < 25 kg. 1
Adolescents (≥13 years) – Start with 2.5 mg once or twice daily (morning and optionally noon). For adolescents weighing < 25 kg, the maximum single dose is 10 mg. 1
Adults – Initiate therapy with 2.5 mg once or twice daily. The usual therapeutic range is 10–50 mg total per day, with a recommended maximum of 40 mg daily (higher doses may be used only with clear documentation). [2][1]

Increase the dose weekly by 2.5–5 mg per dose based on symptom response and tolerability, using 2–3 administrations per day because each dose lasts ≈ 4 hours. The total daily dose is the sum of all individual doses. 1

Baseline assessment – Record blood pressure, pulse, height, and weight; obtain a detailed cardiac history and family history of cardiovascular disease. [1][3]
During titration – Conduct weekly telephone or in‑person contacts; evaluate ADHD symptoms with parent and teacher rating scales; monitor for side effects such as insomnia, reduced appetite, headache, social withdrawal, tics, and weight loss. 1
Maintenance phase –
- Adults: check blood pressure and pulse quarterly.
- Children/Adolescents: check vital signs annually during routine examinations.
- Measure weight at every visit to gauge appetite effects.
- Schedule monthly follow‑up appointments until symptoms are stable. 1

Use the minimum effective dose to start therapy; systematic titration to optimal effect is preferred over strict mg/kg calculations. [1][2]
If the highest recommended dose does not achieve control, consider switching agents or adding psychosocial interventions rather than exceeding the dose. 1
Pitfalls – Do not assume very low doses (e.g., 5 mg/day) are sufficient without proper titration; dextroamphetamine has a greater impact on appetite and sleep than methylphenidate because of its longer half‑life. [2][1]
Drug interactions – Avoid concurrent use with monoamine‑oxidase inhibitors; a 14‑day washout is required before initiating dextroamphetamine. [2][3]

Patients with a history of substance use – Prefer long‑acting formulations that have lower abuse potential; maintain weekly monitoring during titration and monthly follow‑up during maintenance. [2][3]
Comorbid depression or anxiety – Dextroamphetamine can be combined safely with selective serotonin reuptake inhibitors, as no pharmacokinetic interactions have been identified. 3
Comorbid bipolar disorder – Stabilize mood with appropriate mood stabilizers before starting stimulant therapy. 2