The drugs usually prescribed to treat Attention Deficit Hyperactivity Disorder (ADHD) — a class of drugs known as stimulants — are generally effective and safe. Most children and teens (60% to 80%) who take them become less hyperactive and impulsive, better able to focus, and less disruptive at home or school.

Diagnosis of the condition can be difficult, however, and many children and teens taking stimulants either do not have ADHD or have only mild symptoms. They may not need medication. Be sure to get careful diagnosis and a second opinion if you have doubts.

Adults with ADHD also appear to benefit from taking stimulants. But far fewer studies have examined the effectiveness of the medicines in this population.

Our analysis found no evidence that any one stimulant drug is more effective than any other. Each raises different safety issues, however, and these should be carefully evaluated and discussed with your doctor.

Dosing convenience (taking one pill a day instead of two or more) and the period of time that a stimulant pill is active in your body are critical elements of ADHD treatment. The stimulant drugs vary in cost, with the longer lasting pills generally more expensive.   Taking the evidence for effectiveness, safety, cost, and dosing into account, we have chosen the following as Consumer Report Best Buy Drugs to treat ADHD:

• Methylphenidate tablets — 5mg, 10mg and 20mg
• Methylphenidate sustained release tablets or capsules (Metadate ER, Metadate CD, and Methylin ER) — 10mg, 20mg, 30mg
• Dextroamphetamine tablets — 5mg, 10mg
• Dextroamphetamine sustained release or long-acting tablets — 5mg, 10mg and 15mg

These four medicines have been tested by time, and are available in low-cost generic or “branded” generic forms. Their monthly cost ranges from $10 to $86. If you are prescribed a drug for ADHD that costs more than $100 per month or is not a stimulant drug, we advise you to discuss that choice with your doctor.

Methylphenidate (short and long acting) is supported by more evidence than dextroamphetamine. Dextroamphetamine also causes slightly more side effects and has a higher potential for abuse. But all the stimulants can and are being used illegally, mostly by high school and college students seeking an edge in their studies. Parents of teens and college students should monitor their children’s use of these medicines carefully.