Introduction to Stimulants
Cesar A. Soutullo, M.D.
UC-3 Psychopharm Lectures
1. Stimulants
• Use throughout the day & on wk-ends
– Not only during school
– Improve social interact, leisure particip.
– Improve oppositional, aggressive behaviors
• Methylphenidate short acting
• Dextroamphetamine long acting
• Ritalin-SR, Dex-Spans longer
1. Stimulants
• Use throughout the day & on wk-ends
– Not only during school
– Improve social interact, leisure particip.
– Improve oppositional, aggressive behaviors
• Methylphenidate short acting
• Dextroamphetamine long acting
• Ritalin-SR, Dex-Spans longer
Stimulants: Pharmacokinetics
• Ritalin: Liver met, kidney excret
– Peak Serum Level 1.9 hr [0.3 - 4.4 hr]
– SR: 4.7 hr [1.3-8.2 range]
– Half-life: 2-2.5 hrs.
• Dexedrine: Liver met, kidney excret
– Peak: 2 hrs (Spansule 8-10 hr)
– Half-life: 6-8 hr kids / 10-12 adults
Stimulants: Side Effects
• Appetite suppression: HS snack
– Effect on height rarely clinically signif
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Sleep difficulty: dose before 4 pm
 Systolic BP (mild)
Exacerbate Tics & Tourette’s
Psychosis: discontinue
Rebound effects:
– excitability, irritability 4-5 hrs after dose
– give pm dose or use spansules
1.a. Methylphenidate [Ritalin]
• Peak 1-2 hrs, half-life 2.5
• Total daily dose 1 mg/kg/day (0.6-2)
• In >6 y.o. start 5 mg qd or bid (AM & 12)
– raise 5-10 mg/wk, (can add 4 pm dose)
• Tablets: 5, 10, 20 mg
• SR 20 mg
• Max> dose: 60 mg/day
1.b. Dextroamphetamine
[Dexedrine]
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Half-life 6-8 hrs
Optimal dose 0.3-1.5 mg/kg/day
age 3-5 2.5 mg/d,  2.5 once-twice wk
> 6 yo 5 mg/d,  5 mg once-twice wk
Tablets: 5 mg, scored
Spansules: 5, 10, 15 mg
Max dose 40 mg/day
Better for pt. with Seizures
1.c. Adderall [dextr saccharate,
sulph & amphet sulph, aspart]
• Half-life 7-8 hrs
• Dose like Dexedrine
• Tablets 5, 10, 20, 30 mg
1.d Mg Pemoline [Cylert]
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Least abuse potential
Rx once a day 37.5 mg/d
Max dose 112.5 mg/day
Reduced use, Side effects:
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choreoathetoid movements
insomnia
chronic hepatitis
fulminant liver failure (rare)
2. Antidepressants in ADHD
• TCAs: Helpful but caution
– IMI. Cardiac SE,  hyperactivity
1 mg/kg/day & over
– PR , 210 msec, QT < 450 msec HR<130 bpm
– Desipramine: sudden death reports?
• Bupropion: Sz
• SSRI: Not helpful
• Venlafaxine: Improves behavioral Sx?
2.b. Bupropion [Wellbutrin]
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 Hyperactivity-Impulsivity
Improve cognitive performance?
Effects: DA reuptake block
Start 37.5 to 50 mg bid, gradual increase
Seizure risk
– Do not use > 150 mg/dose or 450 mg/day
– Separate doses > 4 hours
3.a. Clonidine [Catapress]
– Presinaptic Alpha-agonist, NE release
–  frustration tolerance,  hyperarousal
–  hyperactivity
• Clonidine+Ritalin: 3 cases sudden death
– EKG, Hx of Syncope, FHx sudden death
• Helpful in ADHD + Tics
• Start Dose 0.05 mg hs (tablets 0.1 mg)
– slow up to 0.15-0.3 mg/day
– Slow D/C, rebound hyypertension
• Skin patch: toxic if eaten or damaged