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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following drugs does not cross placenta?
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The correct answer is  Heparin due to its large molecular size does not cross the placental barrier therefore can be used in pregnancy. From medical pharmacology padmaja 4th edition Page no 335