Stimulants are medications or other compounds (including caffeine, cocaine and nicotine) that stimulate the central nervous system (CNS) in most individuals. Stimulants can be addictive and often are abused. Stimulants have similar effects as amphetamine. They stimulate the brain by increasing the level and effect of the natural neurotransmitters, dopamine, and norepinephrine in the brain (neurotransmitters are chemicals produced by nerves that are released and attach to other nearby nerves as a means of communication among nerves).

The effects of stimulants on the body may include

• increased attention,
• alertness, and
• energy in many people without ADHD.

In people with ADHD, stimulants produce a paradoxical calming effect. This results in a reduction in hyperactivity and an improvement in attention span in many patients. Apart from form their effects on the brain they also increase blood pressure, heart rate, blood glucose, and open up breathing airways. Their exact mechanism of action in treating ADHD is unknown. This article will focus on those stimulants used to treat ADHD.

Approved medical uses for stimulants include

• attention-deficit hyperactivity disorder (ADHD),
• narcolepsy, and
• treatment resistant depression.
• Some formulations are used for treating obesity.

Because of their addictive potential some stimulants are no longer recommended for treating asthma and other nervous system disorders.

Methylphenidate and or amphetamine derivatives are the two types of stimulants (phenethylamine and piperidine classes) used for treating ADHD. Medications used for treating ADHD are available only by prescription. There are no OTC (over-the-counter) stimulants approved for treating ADHD. The following is a list of many brand and generic names of stimulants used for treating ADHD in children and adults:

• Adderall (amphetamine/dextroamphetamine)
• Adderall XR (amphetamine/dextroamphetamine)
• Adzenys XR-ODT (amphetamine)
• Dexedrine (dextroamphetamine)
• Zenzedi (dextroamphetamine)
• Dyanavel XR (amphetamine)
• Evekeo (amphetamine)
• Vyvanse (lisdexamfetamine)
• Desoxyn (methamphetamine)
• ProCentra (dextroamphetamine)
• Aptensio XR (methyphenidate)
• Ritalin (methylphenidate)
• Ritalin SR (methylphenidate)
• Ritalin LA (methylphenidate)
• Concerta (methylphenidate)
• Daytrana (methylphenidate)
• Metadate (methylphenidate)
• Metadate CD (methylphenidate)
• Metadate ER (methylphenidate)
• Methylin (methylphenidate)
• Quillivant XR (methylphenidate)
• QuilliChew ER (methylphenidate)
• Focalin (dexmethylphenidate)
• Focalin XR (dexmethylphenidate)

Common side effects of stimulants used for ADHD management include:

• Abdominal pain
• Headache
• Insomnia
• Loss of appetite
• Weight loss

Other side effects of stimulants medications for ADHD include:

• Anxiety
• Diarrhea
• Dizziness
• Dry mouth
• Dyspepsia
• Emotional irritability
• Fatigue
• Fever
• Nausea
• Nervousness
• Vomiting

Serious side effects of stimulants used for treating ADHD include:

• Infection
• Tachycardia
• Addiction
• Serious allergic reactions
• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Psychotic episodes
• Rhabdomyolysis
• Prolonged erections
• Cardiomyopathy

• Amphetamines should not be taken with monoamine oxidase (MAO) inhibitor drugs including phenelzine (Nardil), tranylcypromine (Parnate), and Zyvox.
• Antacids may increase absorption of amphetamine salts and increase their effectiveness and side effects.
• The effects of stimulants on the CNS can be additive when used with other chemicals and medications that stimulate the CNS, such as caffeine (found in coffee, tea, or cola drinks), and pseudoephedrine or phenylpropanolamine (found in many cough-and-cold preparations).
• The combination of stimulants and monoamine oxidase inhibitors (MAOIs), for example, isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and procarbazine (Matulane), should not be taken with a stimulant since a hypertensive crisis (severely high blood pressure) may occur. Use of amphetamine within 14 days of using MAO inhibitor drugs should be avoided. 
• The blood pressure lowering effects of medications used to treat hypertension may be reduced by stimulants. As a result, blood pressure should be monitored when starting or stopping stimulants in patients who are receiving blood pressure medications.

Stimulants are available as immediate acting or long acting formulations and are available in the following formats:

• Tablets (for example, Adderall, Concerta)
• Capsules (for example, Adderall XR, Ritalin)
• Chewable tablets (for example, Quillichew ER, Methylin)
• Oral solution (for example, Methylin)
• Transdermal Patch (for example, Daytrana)

• Stimulants have not been adequately evaluated in pregnant women. Available evidence suggests that amphetamine type stimulants do not increase the rate of birth defects when used at recommended doses. However, decreased birth weight has been seen in infants whose mothers received dextroamphetamine for weight control.
• There are no controlled studies of stimulants in women who are breastfeeding. There is every little information on the effect of methylphenidate on the developing fetus. Stimulants should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.