Doxylamine: A Review of Pharmacological Properties and Clinical Applications
Abstract
Doxylamine is an antihistamine with a wide range of pharmacological properties and clinical applications. Its chemical structure is closely related to that of diphenhydramine, another antihistamine. Doxylamine has been used to treat numerous conditions, such as allergic rhinitis, pruritus, urticaria, and insomnia. It has also been used to treat nausea and vomiting during pregnancy, as well as motion sickness. Additionally, doxylamine has been studied for its effects on opioid withdrawal and its potential use in the treatment of opioid addiction. Here, we review the pharmacology, clinical applications, safety, and side effects of doxylamine.
Introduction
Doxylamine is an antihistamine with a wide range of pharmacological properties and clinical applications. It is a first-generation antihistamine that is closely related to diphenhydramine in terms of structure and mechanism of action. Its chemical name is 2-(diethylamino)-N-methylbenzamide and its molecular weight is 263.38 g/mol. Doxylamine is used to treat a variety of conditions, including allergic rhinitis, pruritus, urticaria, and insomnia. It has also been used to treat nausea and vomiting during pregnancy, as well as motion sickness. Additionally, doxylamine has been studied for its effects on opioid withdrawal and its potential use in the treatment of opioid addiction. Here, we review the pharmacology, clinical applications, safety, and side effects of doxylamine.
Pharmacology
Doxylamine is structurally related to diphenhydramine and has a similar mechanism of action. It is an H1-receptor antagonist, which means that it blocks the action of histamine, a neurotransmitter involved in the inflammatory response. Doxylamine has a high affinity for the H1 receptor, with an affinity constant (Ki) of 0.3 nmol/L. The potency of doxylamine is comparable to that of diphenhydramine (Ki 0.46 nmol/L).
Doxylamine is rapidly absorbed from the gastrointestinal tract and is widely distributed throughout the body. It is primarily metabolized in the liver and excreted in the urine. The elimination half-life of doxylamine is approximately 3-4 hours.
Clinical Applications
Doxylamine has been used to treat a variety of conditions, including allergic rhinitis, pruritus, urticaria, and insomnia. It has also been used to treat nausea and vomiting during pregnancy, as well as motion sickness. Additionally, doxylamine has been studied for its effects on opioid withdrawal and its potential use in the treatment of opioid addiction.
Allergic Rhinitis: Doxylamine has been used to treat allergic rhinitis, a condition characterized by nasal congestion, sneezing, and runny nose due to an allergic reaction. It can relieve symptoms such as itching, sneezing, and nasal congestion.
Insomnia: Doxylamine has been used to treat insomnia, a condition characterized by difficulty falling asleep and staying asleep. It can help reduce the time it takes to fall asleep and improve the quality of sleep.
Nausea and Vomiting During Pregnancy: Doxylamine has been used to treat nausea and vomiting during pregnancy, a condition known as “morning sickness”. It can help reduce the severity of nausea and vomiting.
Opioid Withdrawal: Doxylamine has been studied for its potential use in the treatment of opioid withdrawal. It has been shown to reduce the severity of opioid withdrawal symptoms such as anxiety, agitation, and muscle aches.
Safety and Side Effects
Doxylamine is generally well-tolerated. The most common side effects include drowsiness, dry mouth, and blurred vision. Rarely, it can cause dizziness, fatigue, and confusion. It should be used with caution in patients with narrow-angle glaucoma, urinary retention, and liver or kidney disease.
Conclusion
Doxylamine is an antihistamine with a wide range of pharmacological properties and clinical applications. It is used to treat a variety of conditions, including allergic rhinitis, pruritus, urticaria, and insomnia. It has also been used to treat nausea and vomiting during pregnancy, as well as motion sickness. Additionally, doxylamine has been studied for its effects on opioid withdrawal and its potential use in the treatment of opioid addiction. In general, doxylamine is well-tolerated, but its use should be used with caution in patients with narrow-angle glaucoma, urinary retention, and liver or kidney disease.
References
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