I added a newline (\n) to the beginning of my prompt. This way I never lose program output -- and also it's easier to see where previous commands begin and end in the scrollback buffer.
zsh prompt:
PROMPT='
%{$prompt_default_color%} %~ %* %{${fg[$prompt_user]}%}%n%{$prompt_default_color%}@%{${fg[$prompt_host]}%}%M%{$prompt_default_color%} ${vcs_info_msg_0_}_
$ %{${fg[default]}%}'