We conducted a systematic review and meta analysis of randomized controlled trials of galantamine hydrobromide in the treatment of mild to moderate dementia. Following a literature search and screening process, we included 15 trials and five companion papers in the review. Moderate-quality evidence suggested galantamine-treated persons generally had better outcomes than placebo-treated persons after a maximum 6-month follow-up. Outcome domains included cognitive function, global function, behaviour and mood, and activities of daily living. The evidence requires careful interpretation because ‘better outcomes’ can mean less deterioration, rather than improvement, relative to placebo. Galantamine has not been shown to halt dementia progression nor reverse disease course. The most frequently reported harms were nausea, diarrhea, and dizziness. Reported rates of these harms were highly variable (range, 0%–40%); reporting was at high risk of bias because authors rarely specified the frequency or timing of harms assessment, nor did they report active methods of collecting harms.