McKenna's Pharmacology for Nursing, 2e

C H A P T E R 2 6 Opioids, opioid antagonists and antimigraine agents 401

Drug therapy across the lifespan

BOX 26.1

Opioids CHILDREN

adverse effects on the fetus.These drugs enter breast milk and can cause opioid effects in the baby, so caution should be used during breastfeeding. Morphine and pethidine are often used for analgesia for labour.The mother should be monitored closely for adverse reactions, and, if the drug is used over a prolonged labour, the newborn infant should be monitored for opioid effects such as respiratory depression. Naloxone should be readily available for the baby if the mother has received an opioid in the hours immediately prior to the birth. OLDER ADULTS Elderly people should be specifically asked whether they require pain medication. Because many older people can recall a time when nurses were able to spend more time with people, they may tend to believe that the nurse will meet their needs. Older people are more likely to experience the adverse effects associated with these drugs, including central nervous system, gastrointestinal and cardiovascular effects. Because older people often have renal or hepatic impairment, they are also more likely to have toxic levels of the drug related to changes in metabolism and excretion.The older person should have safety measures in effect—side rails, call light, assistance to ambulate—when receiving one of these drugs in the hospital setting.

The safety and effectiveness of many of these drugs have not been established in children. If an opioid is used, the dose should be calculated very carefully, and the child should be monitored closely for the adverse effects associated with opioid use. Opioids that have an established paediatric dose include codeine, fentanyl (but not transdermal fentanyl), hydrocodone, pethidine and morphine. Oxycodone and dextropropoxyphene are not recommended for children. Methadone is not recommended as an analgesic in children. If a child older than 16 years of age requires an opioid agonist-antagonist, buprenorphine-naloxone is the preparation of choice. Naloxone is the drug of choice for reversal of opioid effects and opioid overdose in children. ADULTS Adults being treated for acute pain should be reassured that the risk of addiction to an opioid during treatment is remote.They should be encouraged to ask for pain medication before the pain is acute, to get better coverage for their pain. Many institutions allow people to self-regulate intravenous drips to control their pain postoperatively. PREGNANCY AND BREASTFEEDING The opioids are contraindicated or should only be used with caution during pregnancy because of the potential for

TABLE 26.1

DRUGS IN FOCUS Opioids

Drug name

Dosage/route

Usual indications

Opioid agonists alfentanil (Rapifen)

Spontaneous ventilation: 7 mcg/kg by slow IV injection Controlled ventilation: 20-50 mcg/kg by slow IV injection Adult: 15–60 mg PO, IM, IV or SC q 4–6 hours; 10–20 mg PO q 4–6 hours for cough Paediatric: 0.5 mg/kg PO, IM or SC q 4–6 hours; 2.5–10 mg PO q 4–6 hours for cough Adult: 0.05–0.1 mg IM, 30–60 minutes before surgery; 0.002 mg/kg IV or IM during surgery; 0.05–0.1 mg postoperatively; 5 mcg/kg transmucosally; for transdermal patch, calculate the previous day’s opioids need and use table to convert to patch strength; ionic delivery system, 40 mcg over 10 minutes Paediatric (>2 years): 2–3 mcg/kg IM or IV; base transmucosal dose on weight and do not exceed 400 mcg 100 mg PO q 4 hours as needed

Analgesic supplement and anaesthetic induction agent in inpatient surgery

codeine (generic)

Relief of mild to moderate pain; relief of coughing induced by mechanical or chemical irritation of the respiratory tract

dextropropoxyphene (Doloxene)

Relief of mild to moderate pain in adults Special considerations: limit use in suicidal or addiction-prone people For analgesia before, during and after surgery; transdermal patch for management of chronic pain; control of breakthrough pain

fentanyl (Actiq, Duragesic, Sublimaze)

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