How pregnancy can affect medicines

• Pregnancy may change the way your body uses and responds to certain medicines.
• Changes in the medicine dose or additional monitoring may be necessary.

The use of any over-the-counter medicines, supplements, nonprescribed use of medicines or nicotine, cannabis, or other substances during pregnancy should be discussed with your healthcare professional.

Amphetamines

Amphetamines are stimulants that speed up the messages between the brain and body. Some amphetamines such as dextroamphetamine (Adderall XR, Dexedrine Spansule) are prescribed to treat medical conditions such as attention deficit hyperactivity disorder (ADHD), narcolepsy and depression. Other amphetamines are illegal and highly addictive. This includes methamphetamine, also known as meth.

Meth use during pregnancy has been linked to miscarriage, low birth weight, preterm birth, separation of the placenta from the uterus, known as placental abruption, as well as a high blood pressure condition called preeclampsia. Babies who are exposed to meth in the womb may experience withdrawal symptoms after birth that may include jitteriness, drowsiness and trouble breathing. Prenatal exposure to methamphetamine also has been linked to brain development issues in children.

Due to serious health consequences, it's recommended to avoid methamphetamine use. For prescribed amphetamine medicines, discuss the benefits and risks of continuing use during pregnancy with your healthcare professional.

Benzodiazepines

Benzodiazepines are sedatives used to treat conditions such as anxiety, insomnia, alcohol withdrawal and seizures. They also may be used during a procedure or surgery as a part of anesthesia care. Benzodiazepines have sedative and hypnotic effects on the body which reduce anxiety and relax the muscles. As a result, benzodiazepines are often misused and can be addictive.

Studies have shown that benzodiazepine use during pregnancy is unlikely to cause birth defects but may increase the risk of miscarriage, preterm birth and low birth weight. When used regularly during the third trimester, babies are at risk for withdrawal. Symptoms of withdrawal may include:

• Changes in muscle tone.
• Diarrhea.
• Drowsiness.
• Irritability and restlessness.
• Low body temperature.
• Poor feeding.
• Tremor.
• Trouble breathing.
• Vomiting.

Discuss the benefits and risks of taking a benzodiazepine during pregnancy with your healthcare professional.

Gabapentinoids

Gabapentinoids are medicines used to treat seizures and nerve pain. Gabapentinoids include gabapentin (Neurontin) and pregabalin (Lyrica).

Some studies have found that when used during pregnancy, gabapentinoids may cause a slightly higher risk of heart defects in babies. They also may be linked to preterm birth and low birth weight.

If you are taking a gabapentinoid during pregnancy, your healthcare professional may recommend that you increase your folic acid intake.

More research is needed to more clearly understand the effects of gabapentinoid use during pregnancy. Discuss the benefits and risks with your healthcare professional.

Opioids

Opioids are medicines used to relieve pain. They may come from the poppy plant or can be man-made. Opioids travel through the blood and attach to receptors in the brain. This blocks pain messages and can boost feelings of pleasure. However, using opioids often can lead to dependence and addiction.

During pregnancy, opioids cross the placenta. Exposure in the womb can lead to fetal dependence and can cause withdrawal symptoms in the baby after birth, also known as neonatal abstinence syndrome. Symptoms of neonatal abstinence syndrome in the baby may include:

• Diarrhea.
• Fever and blotchy skin.
• Frequent yawning.
• High-pitched crying.
• Jitters.
• Rapid breathing.
• Seizures.
• Tremors.

While opioids rarely cause birth defects, they may increase the risk of miscarriage, stillbirth, poor fetal growth and preterm delivery.

Discuss the benefits and risks of continuing an opioid during pregnancy with your healthcare professional.