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.
Concerta Withdrawal Symptoms: List of Possibilities. 1  Anxiety: Many people experience anxiety when they stop taking Concerta. In some cases the anxiety is severe and can lead to panic attacks. Just realize that this anxiety will not last forever â it is likely a result of neurotransmitter changes.