How long to the effects of ritalin last. 1 Answer - Posted in: ritalin, ritalin la - Answer: In studies with Ritalin LA and Ritalin tablets in adults, methylphenidate . Last reviewed by: Kristi Monson, PharmDSecond, the effects of Ritalin last longer than cocaine or the amphetamines. . Sufficient data on safety and efficacy of long-term use of Ritalin in children are . . . . Ritalin effects ADHD . . This is unfortunate, because Ritalin has been around for a very long time and has a good track ... more