From the FDA Drug Label
If pregnant or breast-feeding ask a health professional before use. The FDA drug label does not answer the question.
From the Research
Tylenol (acetaminophen) is generally considered safe during the third trimester of pregnancy when used as directed, but it should be taken only when necessary and at the lowest effective dose. The recommended dosage is 500-1000 mg every 4-6 hours, not exceeding 4000 mg in 24 hours. While acetaminophen crosses the placenta, extensive research has not shown significant risks to the developing baby when used appropriately in the third trimester 1, 2. However, some recent studies suggest a possible association between prolonged or high-dose acetaminophen use during pregnancy and a slight increase in the risk of childhood asthma or attention issues, though these findings remain inconclusive 3, 2. As with any medication during pregnancy, it's essential to discuss use with your healthcare provider before taking it, especially for chronic pain requiring regular use. Alternative non-medication approaches like rest, proper body positioning, or physical therapy might be worth trying first for minor discomfort. Acetaminophen works by reducing pain signals in the central nervous system and lowering fever, making it effective for headaches, minor aches, and fever during pregnancy without the anti-inflammatory effects that make NSAIDs potentially problematic in late pregnancy. Some studies have investigated the effects of acetaminophen on fetal development, including a study published in 2021 that found exposure to mild analgesics, including acetaminophen, can interfere with early nephrogenesis in human fetal kidneys 4. However, this study focused on the first trimester, and its findings may not be directly applicable to the third trimester. Given the available evidence, it is crucial to use acetaminophen judiciously and only when necessary, weighing the potential benefits against the potential risks. Healthcare providers should inform patients about the potential risks and benefits of acetaminophen use during pregnancy, and patients should be encouraged to use the lowest effective dose for the shortest duration necessary 2.
Key considerations for acetaminophen use in the third trimester include:
- Using the lowest effective dose
- Limiting the duration of use
- Avoiding high-dose or prolonged use
- Discussing use with a healthcare provider, especially for chronic pain
- Exploring alternative non-medication approaches for minor discomfort
- Being aware of the potential risks, including childhood asthma or attention issues, although these findings are inconclusive.