The pulmonic valve is the second valve of the heart. Like the aortic valve, it is also referred to as a semilunar valve, because of its shape. It lies between the right ventricle and the pulmonary artery, which takes blood to the lungs.
Transdermal analgesic patch. A transdermal analgesic or pain relief patch is a medicated adhesive patch used to relieve minor to severe pain.
A patch may have a longer duration of action than an oral medication. Some medications such as estrogen or clonidine patches, can be worn for several days. A Daytrana patch is not supposed to be used for longer than 9 hours. The effect starts about 2 hours after the patch is applied and continues for about 3 hours after the patch is removed. If one wears the patch for 9 hours one gets about 10 hours of significant drug effect. A patch can promote greater flexibility of dose duration. For example, the Daytrana, the methylphenidate patch can be removed earlier on days when one does not need a long duration of action. For children who have problems with appetite suppression, one might remove the patch earlier if the child does not have homework of after-school activities. Elimination of first pass drug metabolism.