Pain Home > Avinza and Pregnancy
In studies on Avinza and pregnancy, a number of problems occurred when morphine (the active ingredient of Avinza) was given to pregnant animals. Problems seen in animal studies include birth defects, encephalopathy, and slow growth, among others. If you are taking Avinza and pregnancy occurs, your healthcare provider will weigh the benefits and potential risks before making a recommendation for your situation.
Avinza® (morphine sulfate ER) is a prescription pain medication. Based on the results of animal studies, the drug may not be safe for use during pregnancy.
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category C is given to medicines that have not been adequately studied in pregnant humans but that do appear to cause harm to the fetus in animal studies. Also, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
When given to pregnant animals in the second trimester, morphine (the active ingredient of Avinza) increased the risk of birth defects (such as skeletal problems) and encephalopathy (brain disease or injury). Interestingly, giving male rats large doses of morphine before mating decreased the litter size. Animal studies also show that morphine may reversibly decrease the size of the brain, testes, and overall body weight of the offspring. Other problems seen in animal studies include slow growth, development, and sexual maturation, as well as decreased male fertility.
Avinza is a narcotic, and using this drug during the end of a pregnancy may cause narcotic withdrawal in the infant after delivery. Such withdrawal symptoms may include:
- Irritability and excessive crying
- Shakiness (tremors)
- Hyperactive reflexes
- Fast breathing
- Increased stools
There is also some thought that chronic use of opioid medications (like Avinza) during pregnancy may increase the risk of sudden infant death syndrome (SIDS).
However, pregnancy Category C medicines, including Avinza, may be given to a pregnant woman if her healthcare provider believes that the benefits to her outweigh any possible risks to her unborn child.