There are two types of Health Spells, positive and negative, those which give healing and those which take it away. The spells here all deal with physical health as well, for the full effect spells from the Spiritual Spells section should be used as well. For example a successful cure spell may help someone's cold, but a protection spell along with the cure will see better benefits.
Spells, especially negative healing spells will obey those with the most power. This means if you cast a hurt spell on someone who is more powerful then you, the spell may have no effect, turn against you, or even heal the person. Spells of similar strength may also lay dormant, not taking effect until another spell wears off.
Remember to always undo spells when you want the effect to end, instead of casting another spell to cancel your spell. Cast spells on spells only lead to problems.