anti histamines 2nd gen Flashcards
What are the common indications for second-generation antihistamines?
A: Second-generation antihistamines (cetirizine/Zirtek/Benadryl Allergy Relief, loratadine/Clarityn, acrivastine/Benadryl Allergy Relief Plus, fexofenadine/Telfast) are used to treat allergic conditions, such as hay fever, urticaria (hives), and allergic rhinitis. They can also be used to treat itching and skin rashes associated with these conditions.
What is the recommended dose of cetirizine for adults?
A: The recommended dose of cetirizine (Zirtek/Benadryl Allergy Relief) for adults is 10 mg once daily. In some cases, a lower dose of 5 mg may be used in patients with impaired kidney function.
What is the recommended dose of loratadine for adults?
A: The recommended dose of loratadine (Clarityn) for adults is 10 mg once daily. In patients with impaired liver function, a lower dose of 5 mg once daily may be used.
What is the recommended dose of acrivastine for adults?
A: The recommended dose of acrivastine (Benadryl Allergy Relief Plus) for adults is 8-12 mg every 8 hours, up to a maximum of 24 mg in 24 hours.
What is the recommended dose of fexofenadine for adults?
A: The recommended dose of fexofenadine (Telfast) for adults is 180 mg once daily. In patients with impaired kidney function, a lower dose of 60 mg once daily may be used.
Which second-generation antihistamine has the shortest onset of action?
A: Acrivastine (Benadryl Allergy Relief Plus) has the shortest onset of action of all the second-generation antihistamines, with effects beginning within 15-30 minutes after dosing.
Which second-generation antihistamine is preferred for use in pregnancy and breastfeeding?
A: Loratadine (Clarityn) and cetirizine (Zirtek/Benadryl Allergy Relief) are generally considered safe for use in pregnancy and breastfeeding, as they have been studied more extensively than other second-generation antihistamines and have a long safety record.
Which second-generation antihistamine is preferred for use in children?
A: Cetirizine (Zirtek/Benadryl Allergy Relief) and loratadine (Clarityn) are both considered safe and effective for use in children over 2 years of age, but doses should be adjusted based on age and weight.
Can second-generation antihistamines be used to treat insomnia?
A: Second-generation antihistamines are less likely to cause drowsiness compared to first-generation antihistamines and are not typically used to treat insomnia.
Can second-generation antihistamines be used to treat anxiety?
A: Second-generation antihistamines do not have significant anxiolytic (anti-anxiety) effects and are not typically used to treat anxiety disorders. Other medications, such as benzodiazepines and selective serotonin reuptake inhibitors (SSRIs), are more commonly used for this indication.
