In Jainism, Chovihar (also spelled Chauvihar or Chovihar) refers to the practice of not consuming any food or water after sunset until sunrise the next day. This is a daily discipline for many Jains, as eating after sunset increases the likelihood of ingesting small organisms, which goes against the principle of ahimsa (non-violence).

Pachkan is the formal vow or resolve taken to observe or break a particular practice. When someone needs to break Chovihar (for example, due to health reasons), they should do so with proper intention and a sense of repentance. The process involves taking a pachkan (pledge or resolve), usually before a Jain monk, nun, or in front of the Tirthankara idol, stating the reason for breaking the Chovihar and resolving to resume it as soon as possible.

Example Pachkan for Breaking Chovihar:

_"Michchhāmi Dukkaḍaṃ. Due to unavoidable reasons (such as illness), I am unable to continue my Chovihar and will be eating/drinking at night. I take this pachkan with a pure mind and will resume my Chovihar as soon as possible. May the Arihantas, Siddhas, and all Sadhus forgive me for this lapse."_

Procedure:

1. State your reason honestly and with humility.
2. Take the pachkan in front of a Jain monk/nun, if possible, or in front of the Tirthankara idol or with folded hands.
3. Express repentance (pratikraman) for breaking the vow.
4. Resolve to resume Chovihar as soon as able.

Note: The exact wording and procedure may vary according to Jain sect (Svetambara or Digambara) and local customs.

Always remember, Jainism emphasizes intention and purity of thought. If breaking a vow becomes necessary, it should be done mindfully and with a sincere heart.