OBJECTIVE Health advice can be framed in terms of prescriptive rules (what people should do, e.g. you should drink alcohol within recommended limits) or proscriptive rules (what people should not do, e.g. you should not drink alcohol above recommended limits). The current research examines the differing effect that these two types of injunction have on participants' moral norms, reactance, attitudes and intentions to consume alcohol within moderation, and their subsequent alcohol consumption. METHODS Participants (N = 529) completed an online questionnaire which asked them to report their previous 7 days' alcohol consumption. They then read either a proscriptive or a prescriptive health message and completed measures of moral norms, reactance, attitudes and intentions to drink alcohol only within recommended limits. Subsequent alcohol consumption was reported 7 days later. RESULTS The results showed that across all participants, the proscriptive message elicited stronger moral norms than did the prescriptive message, which in turn were associated with more positive attitudes and intentions to drink within recommended limits. For male participants who reported drinking more alcohol than recommended at baseline, the proscriptive message elicited more reported alcohol consumption over the subsequent 7 days. CONCLUSIONS Proscriptive messages may be effective at eliciting stronger moral norms to drink within government recommended guidelines. However, reactance may occur for high relevance groups. Practical and theoretical implications are discussed.