Side Effects of Dopamine-Boosting Medications

Dopamine activity can be enhanced in one of four main ways. Medications can stimulate dopaminergic nerve cells to release dopamine into the synapse. This is the way that stimulants such as methylphenidate (Ritalin), dextroamphetamine (Dexe-drine), and dextroamphetamine/amphetamine (Adderall) work. In addition, certain drugs of abuse, notably cocaine and methamphetamine, act in part in this way. Providing more of the raw material that nerve cells use to manufacture dopamine can also increase dopamine activity. This is the approach that neurologists use when they prescribe L-DOPA (Sinemet) to patients with Parkinson s disease. Nerve cells convert L-DOPA into dopamine. L-DOPA otherwise has little place in the treatment of psychiatric disorders. Dopamine activity can also be increased by medications that directly stimulate dopamine receptors. Bromocriptine, another medication used to 

Increasing dopaminergic neurotransmission can cause several side effects including insomnia, irritability, decreased appetite, and nausea. On rare occasions, increasing dopamine tone can trigger paranoia, hallucinations, or involuntary movements known as tics. There has also been some concern that prolonged use of stimulants to treat childhood ADHD can retard growth. 

Psychiatrists most often use these medications to treat ADHD, narcolepsy, and refractory depression. Conservative measures are often sufficient to counteract the side effects of increased dopamine. When insomnia or nausea is a problem, changing the dose schedule can be helpful. Avoiding or reducing evening doses can alleviate insomnia taking the medications after meals can lessen nausea and upset 

TABLE 13.4. Medications that Enhance Dopamine Activity 

Medication Means of Increasing Dopamine (DA) Activity Prominent Effects on Other Transmitters Clinical Uses 

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