alicia asked
If I take two 5 mg of Ritalin at the same time, would that be the same as taking ten mg at once? Also, since one 5 mg of Ritalin lasts 4-6 hours does that mean two would last 8-12 hours?
Answer
Taking two 5 mg Ritalin (methylphenidate) tablets would have the same effect as taking one 10 mg methylphenidate tablet. This does not mean that the effect will last twice as long, however. There is a significant difference in taking 10 mg at one time versus taking 5 mg at two different points. Drug metabolism rarely occurs in a linear manner, instead, is often eliminated in a logarithmic way. This essentially means that the higher concentration of the drug, the faster it gets eliminated. Therefore, taking a 10 mg dose reaches a higher peak concentration, but gets eliminated about as fast as if a 5 mg dose was administered.
Immediate release methylphenidate tablets (Ritalin) reach peak effect in about 2-5 hours and lasts about 3-6 hours. The extended release capsules (Concerta) also reach peak effect in about 2-5 hours, but lasts about 8 hours.
Methylphenidate may be used for attention-deficit hyperactivity disorder (ADHD), narcolepsy, and potentially even depression (off-label indication). ADHD medications require dose titration in order to ensure the best effect. Starting with a low dose and increasing weekly usually produces the best results. Because these medications have known side effects, it is important to allow enough time for the medication to take effect in order to find the right dose. Understanding and communicating with your physician is important when titrating your ADHD medication.
If you feel your dose is not working for you it is worth
discussing with your physician your concerns. The dose may need to be
increased, assuming the dose has been tried for at least a week. Once the dose
is titrated to the right dose, it may be possible to switch to extended-release
capsules (Concerta) to improve convenience and have a more consistent effect. The
recommended maximum dose for Ritalin is considered to be 60 mg. Other options
include changing medications to other stimulants or nonstimulants as you may
respond differently to each drug.
Source: Ritalin
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