Screening and evaluation of fungal resources for loratadine metabolites

Loratadine inhibits Staphylococcus aureus virulence and biofilm formation

“…The present data indicating that loratadine reduces S. aureus virulence and biofilm formation at concentrations R25 mM (9.572 mg/mL) suggest that a typical oral loratadine dosage of a 10-mg tablet once daily, which has been shown to result in a mean plasma C max of 4.64 ng/mL after 10 days (Kosoglou et al, 2000), is far too low a dose to produce a plasma concentration that would inhibit S. aureus virulence and biofilm Furthermore, although loratadine had a strong inhibitory effect on S. aureus biofilm formation in our experiments, like most other compounds that inhibit biofilm formation, it was not effective for eradicating the established biofilm. Moreover, oral loratadine is absorbed via the gastrointestinal tract and then metabolized to desloratadine by isoenzymes of the cytochrome P450 system in the liver (Keerthana and Vidyavathi, 2018). Similar to a previous study (Cutrona et al, 2019), we found that desloratadine did not affect S. aureus biofilm formation.…”

SARS-CoV-2-Triggered Mast Cell Rapid Degranulation Induces Alveolar Epithelial Inflammation and Lung Injury

“…To sought drug candidates that may modulate MC degranulation and consequential cytokine release, we examined known MC stabilizers including the second generation antihistamines Ebastine (Eba) and Loratadine (Lor), which are histamine receptor 1 (HR1) antagonists that are routinely used for the treatment of human allergy 57–61 . Eba (and its main metabolite carebastine) and Lor (and its main metabolite desloratadine) can stabilize MCs and block their release of inflammatory mediators 62–67 .…”

Mast Cell Activation Triggered by Retrovirus Promotes Acute Viral Infection

“…The inflammatory mediators released from MCs can be blocked with a series of MC stabilizers including the higher concentration of second-generation antihistamines ( Negro-Alvarez et al, 1996 ). Ebastine and Loratadine are histamine receptor 1 (HR1) antagonists that are routinely used in the clinics for the treatment of allergy ( Goyal et al, 2017 ; Drummond and Lester, 2018 ; Keerthana and Vidyavathi, 2018 ; Sastre, 2020 ). Ebastine (and its main metabolite carebastine) and Loratadine (and its main metabolite desloratadine) can stabilize MCs to block the release of inflammatory mediators ( Yakuo et al, 1994 ; Wang et al, 2005 ; Xia et al, 2005 ; Palikhe et al, 2009 ; Xie et al, 2017 ; Gamperl et al, 2021 ; Wu et al, 2021 ).…”