Pharmacologic Approaches to Cognitive Dysfunction

While no drugs have been approved to treat chemobrain, the following have shown some effectiveness or mixed results in trials.

> Dexmethylphenidate and methylphenidate are stimulants routinely used in the treatment of attention deficit hyperactivity disorder. Side effects include insomnia, headache, nausea and anorexia.

> Modafinil, a central nervous stimulant, is typically used to treat narcolepsy. It appears to exert its effect through the release of the hormone catecholamine (norepinephrine and dopamine) and histamine. Side effects include depression, fatigue and drowsiness.

> Donepezil acts to reduce inflammation, regulate catecholamine, and enhance certain brain functions. It is most widely used to slow the progression of Alzheimer’s disease-related dementia. Side effects include nausea, vomiting and diarrhea.

> Memantine works to decrease abnormal brain activity. It is used to treat Alzheimer’s disease and is being investigated in patients who receive whole-brain radiation. A study released in August involving 508 patients with brain metastases who received 20 milligrams a day of the drug showed improved cognitive function over time and a reduced rate of decline in memory, executive function and processing speed.

All ESAs work in essentially the same way to stimulate the bone marrow to produce red blood cells, thereby reducing the need for blood transfusions. Trials to evaluate ESAs in cognitive dysfunction have shown conflicting results ranging from no therapeutic value to significant improvement. Thus, due to those inconsistent results and Food and Drug Administration warnings regarding their use, as well as the potential for serious and lifethreatening side effects, including heart attack, stroke and clotting, ESAs are not recommended for addressing cognitive impairment in cancer survivors.