Receiving the Lord

Anyone who is conscious of grave (mortal) sin may not receive Holy Communion without first having been to Confession. Catholics who are in an irregular marital or extra-marital relationship may not receive the Sacrament, but they are urged to approach the priest for a blessing.
With the exception of the elderly and the sick and those who care for them, all Catholics must abstain from all food and drink (with the exception of water) for at least one hour before receiving Holy Communion.
A person who has received Holy Communion may receive it again on the same day, provided that, on the subsequent occasion, there has been attendance at the whole of a Mass. In the case of Holy Viaticum (when the Sacrament is given in danger of death), the obligation to be present at the whole of a Mass ceases.