Aphasia, the loss or impairment of language caused by brain damage, is one of the most devastating
cognitive impairments of
stroke.
Aphasia is present in 21-38% of
acute stroke patients and is associated with high short- and long-term morbidity, mortality and expenditure. Recovery from
aphasia is possible even in severe cases. While speech-
language therapy remains the mainstay treatment of
aphasia, the effectiveness of conventional
therapies has not been conclusively proved. This has motivated attempts to integrate knowledge from several domains in an effort to plan more rational
therapies and to introduce other therapeutic strategies, including the use of intensive
language therapy and pharmacological agents. Several placebo-controlled trials suggest that
piracetam is effective in recovery from
aphasia when started soon after the
stroke, but its efficacy vanishes in patients with chronic
aphasia. Drugs acting on
catecholamine systems (
bromocriptine,
dexamfetamine) have shown varying degrees of efficacy in case series, open-label studies and placebo-controlled trials.
Bromocriptine is useful in acute and chronic aphasias, but its beneficial action appears restricted to nonfluent aphasias with reduced initiation of spontaneous verbal messages.
Dexamfetamine improves language function in subacute
aphasia and the beneficial effect is maintained in the long term, but its use is restricted to highly selected samples. Pharmacological agents operating on the
cholinergic system (e.g.
donepezil) have shown promise. Data from single-case studies, case series and an open-label study suggest that
donepezil may have beneficial effects on chronic poststroke
aphasia. Preliminary evidence suggests that
donepezil is well tolerated and its efficacy is maintained in the long term. Randomised controlled trials of
donepezil and other
cholinergic agents in poststroke
aphasia are warranted.