The most common medications used to treat ADHD are drugs belonging to a category of drugs called psychostimulants. These drugs include amphetamines such as Adderall (mixed amphetamine salts), Adderall XR (mixed amphetamine salts extended-release), Desoxyn (methamphetamine), Dexedrine (dextroamphetamine), Dexedrine Spansules (dextroamphetamine), and Vyvanse (lisdexamfetamine). Many other stimulants contain methylphenidate, including drugs such as Ritalin, Methylin, Concerta, Metadate, Daytrana (methylphenidate transdermal).
Focalin (dexmethylphenidate) and Focalin XR (dexmethylphenidate extended-release) are, simply put, simply more potent forms of methylphenidate also used for ADHD.
Amphetamines work by increasing levels of the monoamines dopamine, norepinephrine, and serotonin. Methylphenidate and dexmethylphenidate have no clinically significant effect on serotonin.
By increasing extra cellular concentrations of monoamines there is increased receptor binding leading to enhanced cellular communication. For the most part the areas of the brain that are most stimulated are the under active areas that control impulse (and other things). As a result the under active areas "wake up" and are better able to control impulse and concentration.
Strattera (atomoxetine) is a non-stimulant FDA approved for ADHD typically used in people who fail to properly respond to stimulants, for people with substance abuse problems, and some doctors used Strattera as a first time treatment despite the fact Strattera is not nearly as effective as stimulants. Strattera is a norepinephrine reuptake inhibitor, more similar to antidepressants than other FDA approved ADHD medication. Strattera acts by inhibiting the norepinephrine transporter (NET), preventing norepinephrine from going back into the pre-synaptic cell which increased receptor binding.
The drugs Catapres (clonidine) and Tenex (guanfacine) are also popular and can be taken alone or more commonly taken with a stimulant. These drugs also reduce side effects like insomnia. The FDA has recently approved
Intuniv (guanfacine extended-release) and Kapvay (clonidine extended-release) for ADHD, particularly when taken with a stimulant.
Off label medication are sometimes used including the antidepressant Wellbutrin (bupropion), and the "wake promoting agents" Provigil, Alertec (modafinil) and Nuvigil (armodafanil). Typically these drugs are only used when traditional stimulants fail or are added to stimulants.
There are a number of other drugs that may be used depending on the severity and symptoms of the ADHD.
Tricyclic antidepressants (TCAs) including Tofranil (imipramine), Norpramin (desipramine), and Aventyl, Pamelor (nortriptyline) have some evidence they are useful for ADHD.
There is no "best" drug as each drug works differently with each individual. In some cases, medication is not effective for unknown reasons but 70-90% of people do respond to medication.
As always talk to your doctor about treatment.