Propranolol is a beta-blocker drug prescribed for the treatment of cardiac issues such as irregular heart rate and hypertension. Propranolol during pregnancy is seldom prescribed since beta-blockers may pose a risk to the developing fetus. The drug may be prescribed as a last resort when other medicines yield no results. You must consult your doctor before consuming propranolol or other beta-blockers to minimize possible side effects. Read on to know about the safety of using propranolol during pregnancy, the dosage instructions, side effects, and dosage precautions that should be kept in mind.
What Is Propranolol?
Propranolol (Innopran XL) is a beta-blocker that is used to treat high blood pressure, anxiety, and migraines (1). Propranolol can especially help in:
Treating irregular heartbeats
Preventing future heart attacks and strokes
Preventing chest pain due to angina
It also helps in reducing symptoms of excessive thyroid hormone in the body. It is available in tablet, capsule, and liquid form.
Is It Safe To Take Propranolol During Pregnancy?
The US Food and Drug Administration has categorized propranolol under “pregnancy category C.” This means animal studies have shown that the drug has adverse effects on the fetus, and there are no well-controlled studies in pregnant women (2). While hypertension and cardiac issues can make pregnancy risky, taking medication that can harm your baby is not a good idea. As there are no well-controlled studies in pregnant women and the available studies suggest adverse effects of propranolol on the developing fetus, this drug should be taken during pregnancy only if the potential benefits outweigh the risks and strictly under the guidance of your physician.
How Does Propranolol Affect Pregnant Women?
An animal study on rats found that oral administration of propranolol through pregnancy led to reduced neonatal weight and litter size. In humans, the observations could be interpreted to the increased muscle tone of the uterus, and instability in blood flow (3). Mothers who were given propranolol Hcl at the time of labor showed signs of bradycardia (slow heart rate), hypoglycemia, and/or respiratory depression (2). Talk to your doctor and discuss if there are any safer alternatives to propranolol.
Recommended Dosage
US FDA recommends the following doses for each condition (4). However, your doctor will decide the dosage after considering your requirements.
The recommended dosage for hypertension is 40mg twice a day, and it is not known to cause any adverse effects during pregnancy (5).
Although the FDA recommends 80mg-320 mg for angina pectoris, studies proved that a dosage of more than 160 mg could cause adverse effects on the fetus. So, professional advice is needed (5).
1mg to 30mg three or four times daily for atrial fibrillation
The initial dosage for myocardial infarction is 40mg, and after one month, it can be 60mg to 80mg.
Initial dosage for migraine is 80mg, but the effective dose range is 160mg or 240mg per day; it should be taken after consulting a medical professional.
Whether taken in the prescribed dosages or otherwise, propranolol can have certain side effects in the patients.
Side Effects Of Propranolol During Pregnancy
Propranolol has some common side effects on the mother (6).
If the mother has an intolerance to propranolol tablets, then she could experience a slow heart rate, low blood pressure, dizziness, light-headedness, blurred vision.
A few common side effects include tiredness, weakness, cold extremities, difficulty in sleeping, irregular heartbeat, Raynaud’s syndrome, and nightmares.
If you do take propranolol during pregnancy and experience any of these symptoms, then stop taking the medication and contact your doctor immediately. This post is for informational purposes only and is not a replacement for a doctor’s consultation. Do not use any medication without talking to your doctor. Also, medications for hypertension and anxiety need to be taken continuously for a certain period. So always discuss with your doctor before starting or stopping the medication and stick to the prescribed dosage.