Dexmethylphenidate and Isoniazid interaction
Dexmethylphenidate and Isoniazid: the Dexmethylphenidate prescribing label flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Dexmethylphenidate (Focalin XR) label · effective 2025-09-23
• Concomitant treatment with monoamine oxidase inhibitors (MAOIs) or within 14 days following discontinuation of treatment with an MAOI, because of the risk of hypertensive crises [see Drug Interactions ( 7.1 )] .
• Concurrent treatment with a monoamine oxidase inhibitor (MAOI), or use of an MAOI within the preceding 14 days ( 4 ).
Intervention Concomitant use of Focalin XR with MAOIs or within 14 days after discontinuing MAOI treatment is contraindicated.
Table 5: Clinically Important Drug Interactions With Focalin XR Monoamine Oxidase Inhibitors (MAOIs) Clinical Impact Concomitant use of MAOIs and CNS stimulants, including Focalin XR, can cause hypertensive crisis.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.