Safety considerations in the management of allergic diseases: focus on antihistamines

Abstract

Second-generation oral antihistamines are the preferred first-line treatment option for allergic rhinitis and urticaria. Patients taking SGAHs report relatively little and mild adverse events even after long-term continuous treatments. An antihistamine should ideally possess high selectivity for the H(1)-receptor, high PrH1R occupancy and low to no BrH1R occupancy.

Topical Promethazine Side Effects: Our Experience and Review of the Literature

“…It can also be a melanogenesis-suppressing agent useful as a skin-beautifying cosmetic, a skin-aging prevention agent, and so forth, by using a phenothiazine compound having remarkable melanogenesis-suppressing effect. Application of PM can be used for treating haemorrhoids with no pain, no side effect, no operation, and no hospitalization, but low cost [14–16]. Promethazine has been used to control extrapyramidal disorders in children caused by metoclopramide and levodopa-induced dyskinesia in patients with Parkinson's disease.…”

The effects of treatment on itch in atopic dermatitis

“…Additionally, the safety of sedating antihistamine use in children has been called into question. A recent review on the safety of antihistamines in the treatment of allergic diseases points out that, despite diphenhydramine being available over-the-counter and widely used in children, practically all of the current treatment guidelines for allergic rhinitis and skin allergies do not recommend the use of first generation sedating antihistamines in children due to the sedative effects and danger of cognitive and developmental impairment (50). …”

[11C]Doxepin binding to histamine H1 receptors in living human brain: reproducibility during attentive waking and circadian rhythm

“…There are many available antihistamines with different sedating properties. Therefore, it is important to develop an objective and reliable method for measuring the strength of such sedative side effects, on which we have conducted numerous PET studies (Tagawa et al, 2001; Yanai et al, 2011, 2012). [ 11 C]Doxepin-PET has been shown to be useful for evaluating their sedating side effects and the mechanisms involved.…”

“…The inhibition of histaminergic activity at the brain H1 receptor level may have some favorable anxiolytic effects, however, more often this is accompanied by unfavorable effects like increased daytime somnolence, impaired memory and learning, decreased attention, and weight gain. The brain H1 receptor occupancy measured by [ 11 C]doxepin-PET is one of the most reliable and objective methods to estimate the sedating properties of antihistamines (Yanai et al, 2011, 2012). A critical step in validating [ 11 C]doxepin to measure the brain H1 receptor occupancy is to evaluate the reproducibility of its binding potential (Bmax/KD) in the different attentive conditions.…”