The percentage of those of Hispanic origin in the United States who were of Mexican background in 2013. Another 9.5 percent were of Puerto Rican background, 3.7 percent Cuban, 3.7 percent Salvadoran, 3.3 percent Dominican and 2.4 percent Guatemalan.
Onset of effects occurs within 30-60 minutes after taking Concerta. After that, duration of action lasts from 8-12 hours. And the average times to reach peak plasma concentrations across all doses of Concerta occur between 6-10 hour s. The average half-life for Concerta in adults is about 3.5 hours.
Learn more: ADHD and the role of dopamine Â». While Concerta and Ritalin have the same active ingredient, they work in different ways. Concerta is a long-acting drug: It increases dopamine steadily. This means that you only need to take it once per day for all-day symptom relief. According to the Cleveland Clinic, Concerta works for 10 to 12 hours.