Every one of the faithful is bound, by command of the Church, to receive commune at least once a year, at Easter time.
“All the faithful of either sex, after they have arrived at the years of discretion, that is, the use of reason, must once a year, at least at Easter, receive the sacrament of the Eucharist, less perchance with the advice of their own priest, for some reasonable cause, they are led to abstain from this reception for a while (Canon 859 §1).”
Moreover, in the case of danger of death, and whatever the cause of the danger, each one is obliged to obtain the help of holy communion which is then received in holy viaticum. That is why all those who take care of the sick, whether corporeal or spiritual, must take care that they not postpone holy viaticum too long, and pay close attention so as to ensure that the sick in danger of death receive it with full consciousness.
It is allowed to receive communion twice on the same day:
—If, having already received communion, a danger of death arises so that the second communion is taken in viaticum;
—If, likewise, the need arises to prevent the profanation of the Blessed Sacrament.
The Catholic Church encourages reception of communion often, even daily, provided that the necessary conditions are met.