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Ritalin LA (Methylphenidate Hydrochloride Extended Release) - Description and Clinical Pharmacology


Ritalin LA®

(methylphenidate hydrochloride) extended-release capsules

Rx only

Prescribing Information


Methylphenidate hydrochloride is a central nervous system (CNS) stimulant.

Ritalin LA® (methylphenidate hydrochloride) extended-release capsules is an extended-release formulation of methylphenidate with a bi-modal release profile. Ritalin LA uses the proprietary SODAS® (Spheroidal Oral Drug Absorption System) technology. Each bead-filled Ritalin LA capsule contains half the dose as immediate-release beads and half as enteric-coated, delayed-release beads, thus providing an immediate release of methylphenidate and a second delayed release of methylphenidate. Ritalin LA 10, 20, 30, and 40 mg capsules provide in a single dose the same amount of methylphenidate as dosages of 5, 10, 15, or 20 mg of Ritalin tablets given b.i.d.

The active substance in Ritalin LA is methyl α-phenyl-2-piperidineacetate hydrochloride, and its structural formula is


Methylphenidate hydrochloride USP is a white, odorless, fine crystalline powder. Its solutions are acid to litmus. It is freely soluble in water and in methanol, soluble in alcohol, and slightly soluble in chloroform and in acetone. Its molecular weight is 269.77.

Inactive ingredients: ammonio methacrylate copolymer, black iron oxide (10 and 40 mg capsules only), gelatin, methacrylic acid copolymer, polyethylene glycol, red iron oxide (10 and 40 mg capsules only), sugar spheres, talc, titanium dioxide, triethyl citrate, and yellow iron oxide (10, 30, and 40 mg capsules only).



Methylphenidate hydrochloride, the active ingredient in Ritalin LA (methylphenidate hydrochloride) extended-release capsules, is a central nervous system (CNS) stimulant. The mode of therapeutic action in Attention Deficit Hyperactivity Disorder (ADHD) is not known. Methylphenidate is thought to block the reuptake of norepinephrine and dopamine into the presynaptic neuron and increase the release of these monoamines into the extraneuronal space. Methylphenidate is a racemic mixture comprised of the d- and l-threo enantiomers. The d-threo enantiomer is more pharmacologically active than the l-threo enantiomer.

Effects on QT Interval

The effect of Focalin XR (dexmethylphenidate, the pharmacologically active d-enantiomer of Ritalin) on the QT interval was evaluated in a double-blind, placebo- and open label active (moxifloxacin)-controlled study following single doses of Focalin XR 40 mg in 75 healthy volunteers. ECGs were collected up to 12 hours postdose. Frederica’s method for heart rate correction was employed to derive the corrected QT interval (QTcF). The maximum mean prolongation of QTcF intervals was <5 ms, and the upper limit of the 90% confidence interval was below 10 ms for all time matched comparisons versus placebo. This was below the threshold of clinical concern and there was no evident-exposure response relationship.



Ritalin LA produces a bi-modal plasma concentration-time profile (i.e., 2 distinct peaks approximately 4 hours apart) when orally administered to children diagnosed with ADHD and to healthy adults. The initial rate of absorption for Ritalin LA is similar to that of Ritalin tablets as shown by the similar rate parameters between the 2 formulations, i.e., initial lag time (Tlag), first peak concentration (Cmax1), and time to the first peak (Tmax1), which is reached in 1-3 hours. The mean time to the interpeak minimum (Tminip), and time to the second peak (Tmax2) are also similar for Ritalin LA given once daily and Ritalin tablets given in 2 doses 4 hours apart (see Figure 1 and Table 1), although the ranges observed are greater for Ritalin LA.

Ritalin LA given once daily exhibits a lower second peak concentration (Cmax2), higher interpeak minimum concentrations (Cminip), and less peak and trough fluctuations than Ritalin tablets given in 2 doses given 4 hours apart. This is due to an earlier onset and more prolonged absorption from the delayed-release beads (see Figure 1 and Table 1).

The relative bioavailability of Ritalin LA given once daily is comparable to the same total dose of Ritalin tablets given in 2 doses 4 hours apart in both children and in adults.

Figure 1.  Mean Plasma Concentration Time-Profile of Methylphenidate After a Single Dose of Ritalin LA 40 mg q.d. and Ritalin 20 mg Given in Two Doses Four Hours Apart

Figure 1. Mean Plasma Concentration Time-Profile of Methylphenidate After a Single Dose of Ritalin LA 40 mg q.d. and Ritalin 20 mg Given in Two Doses Four Hours Apart

Table 1. Mean ± SD and Range of Pharmacokinetic Parameters of Methylphenidate After a Single Dose of Ritalin LA and Ritalin Given in Two Doses 4 Hours Apart
a N=15
Population Children Adult Males
10 mg & 10 mg
Ritalin LA
20 mg
10 mg & 10 mg
Ritalin LA
20 mg
N 21 18 9 8
Tlag (h) 0.24 ± 0.44 0.28 ± 0.46 1.0 ± 0.5 0.7 ± 0.2
0 - 1 0 - 1 0.7 - 1.3 0.3 - 1.0
Tmax1 (h) 1.8 ± 0.6 2.0 ± 0.8 1.9 ± 0.4 2.0 ± 0.9
1 - 3 1 - 3 1.3 - 2.7 1.3 - 4.0
C max1 (ng/mL) 10.2 ± 4.2 10.3 ± 5.1 4.3 ± 2.3 5.3 ± 0.9
4.2 - 20.2 5.5 - 26.6 1.8 - 7.5 3.8 - 6.9
T minip (h) 4.0 ± 0.2 4.5 ± 1.2 3.8 ± 0.4 3.6 ± 0.6
4 - 5 2 - 6 3.3 - 4.3 2.7 - 4.3
C minip (ng/mL) 5.8 ± 2.7 6.1 ± 4.1 1.2 ± 1.4 3.0 ± 0.8
3.1 - 14.4 2.9 - 21.0 0.0 - 3.7 1.7 - 4.0
Tmax2 (h) 5.6 ± 0.7 6.6 ± 1.5 5.9 ± 0.5 5.5 ± 0.8
5 - 8 5 - 11 5.0 - 6.5 4.3 - 6.5
Cmax2 (ng/mL) 15.3 ± 7.0 10.2 ± 5.9 5.3 ± 1.4 6.2 ± 1.6
6.2 - 32.8 4.5 - 31.1 3.6 - 7.2 3.9 - 8.3
AUC (0-∞) 102.4 ± 54.6 86.6 ± 64.0a 37.8 ± 21.9 45.8 ± 10.0
(ng/mL x h-1) 40.5 - 261.6 43.3 - 301.44 14.3 - 85.3 34.0 - 61.6
t1/2 (h) 2.5 ± 0.8 2.4 ± 0.7a 3.5 ± 1.9 3.3 ± 0.4
1.8 - 5.3 1.5 - 4.0 1.3 - 7.7 3.0 - 4.2

Dose Proportionality

After oral administration of Ritalin LA 20 mg and 40 mg capsules to adults there is a slight upward trend in the methylphenidate area under the curve (AUC) and peak plasma concentrations (Cmax1 and Cmax2).


Binding to plasma proteins is low (10%-33%). The volume of distribution was 2.65±1.11 L/kg for d-methylphenidate and 1.80±0.91 L/kg for l-methylphenidate.


The absolute oral bioavailability of methylphenidate in children was 22±8% for d-methylphenidate and 5±3% for l-methylphenidate, suggesting pronounced presystemic metabolism. Biotransformation of methylphenidate by the carboxylesterase CES1A1 is rapid and extensive leading to the main, de-esterified metabolite α-phenyl-2-piperidine acetic acid (ritalinic acid). Only small amounts of hydroxylated metabolites (e.g., hydroxymethylphenidate and hydroxyritalinic acid) are detectable in plasma. Therapeutic activity is principally due to the parent compound.


In studies with Ritalin LA and Ritalin tablets in adults, methylphenidate from Ritalin tablets is eliminated from plasma with an average half-life of about 3.5 hours, (range 1.3-7.7 hours). In children the average half-life is about 2.5 hours, with a range of about 1.5-5.0 hours. The rapid half-life in both children and adults may result in unmeasurable concentrations between the morning and mid-day doses with Ritalin tablets. No accumulation of methylphenidate is expected following multiple once a day oral dosing with Ritalin LA. The half-life of ritalinic acid is about 3-4 hours.

The systemic clearance is 0.40 ± 0.12 L/h/kg for d-methylphenidate and 0.73 ± 0.28 L/h/kg for l-methylphenidate. After oral administration of an immediate release formulation of methylphenidate, 78%-97% of the dose is excreted in the urine and 1%-3% in the feces in the form of metabolites within 48-96 hours. Only small quantities (<1%) of unchanged methylphenidate appear in the urine. Most of the dose is excreted in the urine as ritalinic acid (60%-86%), the remainder being accounted for by minor metabolites.

Food Effects

Administration times relative to meals and meal composition may need to be individually titrated.

When Ritalin LA was administered with a high fat breakfast to adults, Ritalin LA had a longer lag time until absorption began and variable delays in the time until the first peak concentration, the time until the interpeak minimum, and the time until the second peak. The first peak concentration and the extent of absorption were unchanged after food relative to the fasting state, although the second peak was approximately 25% lower. The effect of a high fat lunch was not examined.

There were no differences in the pharmacokinetics of Ritalin LA when administered with applesauce, compared to administration in the fasting condition. There is no evidence of dose dumping in the presence or absence of food.

For patients unable to swallow the capsule, the contents may be sprinkled on applesauce and administered (see DOSAGE AND ADMINISTRATION).

Alcohol Effect

Alcohol may exacerbate the adverse CNS effects of psychoactive drugs, including Ritalin. It is therefore advisable for patients to abstain from alcohol during treatment. An in vitro study was conducted to explore the effect of alcohol on the release characteristics of methylphenidate from the Ritalin LA 40 mg capsule dosage form. At an alcohol concentration of 40% there was a 98% release of methylphenidate in the first hour. The results with the 40 mg capsule are considered to be representative of the other available capsule strengths.

Special Populations

Age: The pharmacokinetics of Ritalin LA was examined in 18 children with ADHD between 7 and 12 years of age. Fifteen of these children were between 10 and 12 years of age. The time until the between peak minimum, and the time until the second peak were delayed and more variable in children compared to adults. After a 20-mg dose of Ritalin LA, concentrations in children were approximately twice the concentrations observed in 18 to 35 year old adults. This higher exposure is almost completely due to the smaller body size and total volume of distribution in children, as apparent clearance normalized to body weight is independent of age.

Gender: There were no apparent gender differences in the pharmacokinetics of methylphenidate between healthy male and female adults when administered Ritalin LA.

Renal Insufficiency: Ritalin LA has not been studied in renally-impaired patients. Renal insufficiency is expected to have minimal effect on the pharmacokinetics of methylphenidate since less than 1% of a radiolabeled dose is excreted in the urine as unchanged compound, and the major metabolite (ritalinic acid), has little or no pharmacologic activity.

Hepatic Insufficiency: Ritalin LA has not been studied in patients with hepatic insufficiency. Hepatic insufficiency is expected to have minimal effect on the pharmacokinetics of methylphenidate since it is metabolized primarily to ritalinic acid by nonmicrosomal hydrolytic esterases that are widely distributed throughout the body.


Ritalin LA (methylphenidate hydrochloride) extended-release capsules was evaluated in a randomized, double-blind, placebo-controlled, parallel group clinical study in which 134 children, ages 6 to 12, with DSM-IV diagnoses of Attention Deficit Hyperactivity Disorder (ADHD) received a single morning dose of Ritalin LA in the range of 10-40 mg/day, or placebo, for up to 2 weeks. The doses used were the optimal doses established in a previous individual dose titration phase. In that titration phase, 53 of 164 patients (32%) started on a daily dose of 10 mg and 111 of 164 patients (68%) started on a daily dose of 20 mg or higher. The patient’s regular schoolteacher completed the Conners ADHD/DSM-IV Scale for Teachers (CADS-T) at baseline and the end of each week. The CADS-T assesses symptoms of hyperactivity and inattention. The change from baseline of the (CADS-T) scores during the last week of treatment was analyzed as the primary efficacy parameter. Patients treated with Ritalin LA showed a statistically significant improvement in symptom scores from baseline over patients who received placebo. (See Figure 2.) This demonstrates that a single morning dose of Ritalin LA exerts a treatment effect in ADHD.

Figure 2.  CADS-T Total Subscale-Mean Change from Baseline*

Figure 2. CADS-T Total Subscale-Mean Change from Baseline*

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