Related Experiment Video
Updated: Jun 13, 2026

Acupoint Catgut Embedding Therapy in Traditional Chinese Medicine for Managing Allergic Rhinitis
Published on: December 20, 2024
Safety of antihistamines during pregnancy and lactation
Question:
Many of my pregnant and breastfeeding patients suffer from allergies and frequently ask me about the safety of antihistamines during pregnancy and breastfeeding. Should I advise them to use the older sedating medications? I have heard that they might be safer than the newer nonsedating class of drugs. Or have the newer ones been studied as well?
Answer:
First-generation antihistamines are considered safe to use during pregnancy. There are relatively fewer data on the nonsedating second-generation antihistamines; however, published studies are reassuring. All antihistamines are considered safe to use during breastfeeding, as minimal amounts are excreted in the breast milk and would not cause any adverse effects on a breastfeeding infant.
Related Concept Videos
Upper Respiratory Drugs: Antitussives, Expectorants, and Mucolytics
Antitussives include codeine, dextromethorphan (Robitussin), and benzonatate (Tessalon). Codeine and dextromethorphan exert their effects centrally by suppressing the cough reflex center in the medulla. Benzonatate operates peripherally within the respiratory tract by anesthetizing...
Upper Respiratory Drugs: First and Second-Generation Antihistamines
Histamine binds to specific receptor sites, known as H1 receptors, on tissue cells, triggering inflammation and swelling. Antihistamines combat these effects by competing with histamine for these receptor sites. By...
Chemotherapy-Induced Nausea and Vomiting: 5-HT3 Receptor Antagonists
Cholinergic Antagonists: Pharmacokinetics
Factors Affecting Drug Response: Overview
Sedatives and Hypnotics Drugs: Miscellaneous Agents
Melatonin congeners like ramelteon (Rozerem) and tasimelteon (Hetlioz) selectively bind to melatonin receptors (MT1 and MT2) and thus mimic the actions of melatonin, a hormone that regulates sleep-wake cycles. Tasimelteon is primarily used for non-24-hour sleep-wake disorder, common in blind patients. They are also used to treat conditions like insomnia...
