Ivermectin has gained public attention, prompting questions about its safety, especially during pregnancy. This article clarifies existing information and official recommendations.
Understanding Ivermectin
Ivermectin is an antiparasitic drug discovered from a soil microbe in the 1970s. It was first used in veterinary medicine, then approved for human use in 1987. Its primary purpose in humans is to treat certain parasitic infections, such as onchocerciasis (river blindness) and strongyloidiasis. Topical forms are also approved for head lice and rosacea.
The medication works by targeting specific ion channels in parasite nerve and muscle cells. This action increases chloride ion flow, leading to parasite paralysis and death. Ivermectin’s selective action is due to differences in these channels between parasites and mammals, and its limited ability to cross the human blood-brain barrier at therapeutic doses.
Safety Data and Official Guidance for Pregnant Women
Scientific investigations into ivermectin’s effects during pregnancy include animal studies and human observations. In animal models, high doses (often 10 to 100 times human recommendations) have shown evidence of causing developmental abnormalities. These effects were typically observed at doses that also caused adverse effects in the pregnant animals themselves.
Human data on ivermectin use during pregnancy are limited, primarily from observational studies and one randomized controlled trial. These studies largely involved women inadvertently exposed during mass drug administration campaigns. Available human data did not consistently show an increased risk of neonatal deaths, preterm births, or low birth weight. However, evidence regarding potential increases in spontaneous abortions, stillbirths, or congenital anomalies remains inconclusive due to small case numbers and low certainty.
Official guidance from health authorities reflects this limited data. The U.S. Food and Drug Administration (FDA) classifies ivermectin as Pregnancy Category C, indicating adverse effects in animal studies but no adequate human studies. It suggests use only if potential benefit justifies potential risk to the fetus. Manufacturers generally advise against its use during pregnancy, and global health organizations like the World Health Organization (WHO) recommend excluding pregnant women from mass drug administration programs due to insufficient safety data.
Potential Effects on Mother and Fetus
Animal studies using high ivermectin doses have shown associations with specific developmental issues in offspring, including abnormalities such as cleft palate, skeletal malformations, and heart defects. Ivermectin can also influence protective barriers that limit drug entry into the fetus, and changes during gestation might affect the amount of drug reaching the developing fetus.
While human studies have not definitively linked therapeutic doses of ivermectin to adverse effects on maternal health during pregnancy, general side effects can occur. These may include stomach discomfort, skin rashes, itching, dizziness, and issues affecting the nervous system. Rat studies have observed neonatal toxicity, primarily from exposure through maternal milk after birth due to higher concentrations in breast milk and a more permeable blood-brain barrier in early life pups.
Important Considerations Before Use
Given the limited human data and concerns from animal studies, consulting a healthcare provider is important before considering any medication during pregnancy. Medical professionals can assess potential benefits versus risks. This evaluation considers the specific type and severity of parasitic infection, stage of pregnancy, and available alternative treatments.
Self-medication with ivermectin, or any drug, is strongly discouraged, especially during pregnancy. Without proper medical guidance, incorrect dosing could lead to adverse effects for both the pregnant individual and the developing fetus. More extensive and controlled human studies are needed to provide a clearer understanding of ivermectin’s safety profile during pregnancy.