Without this special delivery-system tablet, methylphenidate doesn't stay in the bloodstream for long. That's why many children need to take medication two or three times a day. Even with Ritalin SR, which has a longer duration of action than regular Ritalin, peak concentrations occur at four hours and, for many children, it has worn off significantly by the early afternoon. This new formulation in Concerta was designed to last all day, even through the late afternoon hours when children are doing their homework.
Studies that compared Concerta to a placebo showed that children taking Concerta had a significant reduction in inattention and overactivity. Studies done to monitor blood levels of the drug showed steadier levels for a longer duration in patients taking Concerta versus those taking standard methylphenidate. There are no studies, however, showing a significant difference in teacher ratings of ADHD symptoms in children on standard methylphenidate vs. Concerta. The presumption is that if the drug levels don't fluctuate as much, and it lasts for a longer time, then it will improve control of the ADHD symptoms -- but I could not find proof of this.
In Concerta's clinical trials, the type of side effects seen were similar to what has been seen for traditional methylphenidate: headaches, stomach pain, loss of appetite, and insomnia. An important difference between this and the older medication is that the Concerta tablet isn't completely digested, even though all of the medication is released. The remnants of the tablet can often be seen in the stools. This isn't usually a problem, but Concerta isn't recommended for children who have any type of severe gastrointestinal narrowing. Concerta hasn't been studied in children under six years of age, so it's not recommended for use in that age group.
Since the drug was just approved, most physicians don't yet have enough experience with it to make specific recommendations. It sounds like a great innovation but may have drawbacks. For children who have difficulty with their ADHD symptoms later in the day, or have difficulty taking medication, a once-a-day dosage may be the perfect solution. For children who have less need for the drug outside of school hours, it may not make sense to give something that lasts for 12 hours. Also, we don't know if there is any long-term effect of having methylphenidate in your bloodstream for many more hours per day.
Keep in mind that this new formulation is more expensive than generic methylphenidate. When I priced it at our local pharmacy it was about $40 to $55 more per month. Concerta comes in 18 mg, 36 mg, and 54 mg tablets.
If you are interested in this new medication, you should talk with your child's doctor, and decide together if it's worth trying.