Skip to main content

Which anti-thyroid drug is safe in pregnancy?

management of Hyperthyroidsm in pregnancy, which antithyroid drug is safer in pregnancyHyperthyroidism is a condition in which thyroid gland starts to secrete an increased amount of thyroxine in the blood. This, in turn, produces several effects in the body, including, palpitations, weight loss, increased appetite, heat intolerance, sleeplessness, generalized weakness and abortions. There are various causes that are responsible for this increased production of thyroxine by the thyroid gland. We will not go into this detail in this article but have explained it in a separate article, the link of which is stated below.
Thyroid Diseases, an overview
Hyperthyroidism in pregnancy should be treated, because it may result in fetal abnormalities. The thyroid hormone T3 and T4 crosses the placenta in small amounts. The amount of diffusion across the placenta decreases with the age of the pregnancy. But still, it may cross in significant amounts. The thyrotropin-releasing hormone and thyroid stimulating immunoglobulins (which are responsible for maternal hyperthyroidism) and beta blockers (which are given in the treatment of hyperthyroidism) readily cross the placenta. So beta-blockers should be avoided in a pregnant thyrotoxic woman. There are three drugs that can be used to treat hyperthyroidism, Carbimazole, Methimazole and Propylthiouracil. Carbimazole and Methimazole cross the placenta and may cause fetal hypothyroidism and abnormalities. The risk is higher with the use of Methimazole. Propylthiouracil has shown to have a much safer profile in pregnancy and can be used. But the lowest possible dose should be given.
If a pregnant woman is severely thyrotoxic, then subtotal or near-total thyroidectomy may be used as an option in selective patients.
Antithyroid drugs are secreted in breast milk, so breastfeeding should be avoided if the mother is taking antithyroid drugs.
In the fetus, the thyroid gland follicles and colloid start to appear in the 10th – 12th week of pregnancy. So before 10 weeks, antithyroid drugs don’t do any harm to the fetus but after that one should be very careful.

    1. Drug therapy for hyperthyroidism in pregnancy: safety issues for mother and fetus. Atkins P, Cohen SB, Phillips BJ.  URL:
    2. American Thyroid Association: How should hyperthyroidism in pregnancy be managed? URL:


Popular posts from this blog

Human Parasites, Types of Parasites, and Classification

Parasite: A parasite is a living organism which gets nutrition and protection from another organism where it lives. Parasites enter into the human body through mouth, skin and genitalia. In this article, we will generally discuss the types and classification of parasites. It is important from an academic point of view. Those parasites are harmful, which derives their nutrition and other benefits from the host and host get nothing in return but suffers from some injury. Types of Parasites Ecto-parasite: An ectoparasite lives outside on the surface of the body of the host. Endo-parasite: An endo-parasite lives inside the body of the host, it lives in the blood, tissues, body cavities, digestive tract or other organs. Temporary parasite: A temporary parasite visits its host for a short period of time. Permanent parasite: Permanent parasite lives its whole life in the host. Facultative parasite: A facultative parasite can live both independently and dependently. It lives in the

How to taper off, wean off beta blocker, atenolol, Propranolol, Metoprolol

Beta blockers include, atenolol (Tenormin), propranolol (Inderal ) and metoprolol (Lopressor) and are used to treat high blood pressure, certain cardiac problems, migraine and few other conditions. People usually take atenolol, propranolol or metoprolol for many years as a treatment of high blood pressure or after having an episode of heart attack . Sometimes, it becomes necessary to withdraw these beta blockers due to their potential side effects that trouble the patients or sometimes doctor wants to change the drug and shift the patient to some other anti-hypertensive medicine. No matter whatever the cause is, whenever, a patient who has been using a beta blocker for a long period of time, and he needs to be stopped from further usage of that beta blocker, must not stop taking it. One should taper off the dose of a beta blocker. Now a question arises how to wean off or taper off a beta blocker? The method of tapering off beta blocker varies from individual to individual. Allow you

Difficulty in standing up from a sitting or squatting position, Causes & Solution

People who feel it difficult to stand up from a sitting or squatting position may have problem in one or more of the following structures. 1. Knee joint 2. Muscles of legs, thighs or buttock 3. Muscles of arms 4. Cerebellum Let’s now explain one by one, what kind of problems in above structures may cause difficulty in standing up from a sitting or squatting position. 1. How do problems in knee joints lead to difficulty in standing up? Knee joint is one of the primary and most affected joint that takes part in standing up. Other joints that take part are hip, ankle, knee, elbow, wrist and shoulder joint. Knee joint gets the most strain , and also knee joint is comparatively less supported. That’s why usually it’s the knee joint that starts to cry first because of arthritis. Knee joint arthritis causes long term knee pain , that makes the movement difficult at knee joint. Arthritis also makes the knee joint stiffer and slower and its range of motion also decreases. All these affects coll