Immediate-release methylphenidate for attention deficit hyperactivity disorder (ADHD) in adults

Area of Science:

• Neuroscience
• Psychiatry
• Clinical Pharmacology

Background:

• Attention deficit hyperactivity disorder (ADHD) affects children, adolescents, and adults, with methylphenidate often a first-line treatment in some countries.
• Evidence regarding the efficacy and adverse events of immediate-release (IR) methylphenidate for adult ADHD is limited and debated.

Purpose of the Study:

• To evaluate the efficacy and harms of IR methylphenidate in treating ADHD in adults.
• To assess effects on ADHD symptoms, clinical impression, functioning, anxiety, and depression.

Main Methods:

• Systematic review of randomized controlled trials (RCTs) comparing IR methylphenidate with placebo or other interventions.
• Searched multiple databases and trial registers, including regulatory agency reports.
• Extracted data on efficacy and harms, calculating mean differences and risk ratios with 95% confidence intervals.

Main Results:

• Very low-certainty evidence suggests IR methylphenidate may reduce ADHD symptoms compared to placebo, but findings are uncertain.
• IR methylphenidate use increased the risk of gastrointestinal complications and loss of appetite compared to placebo.
• Evidence for effects on anxiety, depression, and comparisons with lithium was uncertain or of very low certainty.
• Trials had high risk of bias, with concerns about selective reporting and vested interests.

Conclusions:

• No certain evidence supports IR methylphenidate's efficacy in reducing adult ADHD symptoms compared to placebo or lithium.
• Adults treated with IR methylphenidate face increased risks of gastrointestinal and metabolic harms.
• Clinicians should carefully consider the appropriateness of prescribing IR methylphenidate due to limited efficacy and increased risks.