Pain Medications (cont.)

What are the warnings/precautions with pain medications?

Acetaminophen can be toxic to the liver and should be used with caution, if at all, in people with liver disease. The maximum recommended dose of acetaminophen is four grams per 24 hours, but moderate to heavy alcohol drinkers need to have the dosage adjusted downward.

Use of salicylates, including aspirin, in children and adolescents under 19 years of age may increase the risk of Reye syndrome, an often fatal disorder that develops after a viral illness.

NSAIDs may cause bleeding in the stomach. To reduce this possibility, they should be taken with food. These drugs may cause kidney failure in those with kidney or liver disease. Also, NSAIDs increase the risk of cardiovascular events.

Use of opioid analgesics may result in dependency and tolerability to therapeutic effects. Operating a motor vehicle or machinery may be dangerous while using these pain medications because they can cause drowsiness. Opioids may cause respiratory depression. Mixing opioids with alcohol or certain other centrally acting drugs could result in additive effects.

Death and serious side effects have occurred with the use of fentanyl transdermal patches. Fentanyl patches are not recommended as starting therapy in inexperienced opiate users. Heat from the sun, hot baths, or heating pads can increase the speed of fentanyl release from patches.

Fentanyl buccal tablets have just one indication: treatment of breakthrough pain in cancer patients who are using and who have grown tolerant to opiates. Inappropriate use of fentanyl buccal tablets has resulted in death.

Methadone can negatively affect the heart. Patients slated for methadone therapy should first have an EKG to check for abnormalities. Methadone interacts with many drugs, including some herbs and non-prescription products. Patients should check with their physicians before taking any other drug with methadone.

Most muscle relaxants cause drowsiness. Patients should be careful operating machinery or motor vehicles. Metaxalone and chlorzoxazone (Parafon Forte) should be used with caution in people with liver disease. Dantrolene (Dantrium IV, Dantrium Capsules)  can be toxic to the liver. Carisoprodol use may result in dependence.

Anxiolytics or anti-anxiety medications cause drowsiness, so care should be exercised when operating a motor vehicle or machinery. Patients should be weaned off of benzodiazepines. Sudden withdraw can result in seizures and possibly death.

Some antidepressant medications may cause drowsiness. Antidepressants interact with a wide array of drugs, sometimes with fatal results. Patients with cardiac disease may need to avoid the use of tricyclic antidepressants. Patients using venlafaxine should be monitored for hypertension.

Patients using anticonvulsants as well as antidepressants should be monitored for signs and symptoms of suicidal thoughts.

Orally administered corticosteroids for acute inflammation should not, in general, be suddenly withdrawn. Doses are customarily tapered down over time and patients must follow instructions exactly.