3.3.3.2 Rectal
The rectal route may be used when patients have nausea or vomiting or are
fasting either preoperatively or postoperatively. The rectal route is
contraindicated if there are lesions of the anus or rectum because placement of
the suppository will cause pain. This route is also not useful if there is
diarrhea or in elderly or infirm patients who are physically unable to place
the suppository.
There are commercially available suppositories of morphine, hydromorphone, and
oxymorphone. Medications can also be placed in a colostomy or similar stomp,
provided that the flow of effluent is slow enough to allow the drug to be
absorbed via the mucosa (McCaffery, Martin, and Ferrell, 1992). When converting
from the oral to the rectal route, start with the same amount as the oral dose
and titrate as needed.
Administration Methods
Oral
Transdermal
Nasal
Intravenous or Subcutaneous
Intraventricular
Patient-Controlled Analgesia (PCA)
Adjuvant Drugs
Index