Related Experiment Video
Updated: May 22, 2026

Acupoint Catgut Embedding Therapy in Traditional Chinese Medicine for Managing Allergic Rhinitis
Published on: December 20, 2024
A review of antihistamines used during pregnancy
Sumit Kar1, Ajay Krishnan, K Preetha
1Department of Dermatology, Venereology and Leprosy, Mahatma Gandhi Institute of Medical Sciences, Sewagram, Wardha, Maharashtra, India.
Abstract:
Antihistamines are one of the most common drugs that are used extensively in various dermatological and nondermatological conditions. The use of H-1-antihistamines during pregnancy has been very controversial due to possible teratogenic effects of these drugs. None of the antihistamines available today have been categorized as safe during pregnancy. Control studies are available for certain first generation drugs regarding their safety in pregnancy, but the newer agents require further studies to be declared safer in pregnancy. A few drugs are comparatively safer to use in pregnancy than others. Every drug used in pregnancy carries a risk for teratogenicity and careful risk/benefit assessment should be done before prescribing them.
Related Concept Videos
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...
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...
Cholinergic Antagonists: Therapeutic Uses
Respiratory Tract: Ipratropium, aclidinium, and tiotropium treat asthma, chronic bronchitis, and chronic obstructive pulmonary disease (COPD). They protect against bronchoconstriction caused by irritants like cigarette smoke, sulfur dioxide, and ozone. They also help reduce nasopharyngeal secretions in common...
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...
Cholinergic Antagonists: Pharmacokinetics
Antiasthma Drugs: Muscarinic Receptor Antagonists
Antimuscarinic agents compete with ACh for the same binding site on the muscarinic receptors. By binding to these receptors, they inhibit the downstream effects of ACh and block the parasympathetic...
