Betahistine dihydrochloride or betahistine mesilate: two sides of the same coin or two different coins

The antivertigo drug betahistine exerts a histamine modulatory action in the vestibular system and the brain. It is marketed both as the dihydrochloride and the mesilate salt in India. We conducted a published literature based systematic review to ascertain differences, in any, between the salt and ester forms of the drug. Search of the Medline database was supplemented by searching through references in full text papers and retrieving summary of product characteristic literature. Although the weight of published evidence is greater for betahistine dihydrochloride, in the absence of head-to-head studies comparing the efficacy of the two formulations in Ménière's disease and other vertigo disorders of vestibular origin, it is not possible to conclude that there are definite differences in this regard. However, potentially relevant differences exist to suggest that the two forms are not interchangeable for the treatment of vestibular dysfunction. Molecular weight comparison indicates that the pill burden would be higher for betahistine mesilate for delivering equivalent doses. There could be ethnically influenced differences in pharmacokinetic behavior. There are concerns of potential long-term DNA toxicity due to mesilate ester contaminants during production of betahistine mesilate, which is not there for the hydrochloride form. Detailed post-marketing surveillance data exists only for the dihydrochloride salt. Otorhinolaryngologists and other physicians seeking to optimize treatment with betahistine should be aware of these differences

Ethanolic extract of Piper betle Linn. leaves reduces nociception via modulation of arachidonic acid pathway

Objectives: The objective of this study was to evaluate the peripheral analgesic effect of Piper betle leaf extract (PBE) along with establishing its putative mechanism of action. Materials and Methods: Male Swiss albino mice after pre-treatment (1 h) with different doses of PBE were injected 0.8% (v/v) acetic acid i.p.; the onset and number of writhes were noted up to 15 min. To evaluate the mechanism of action, the murine peritoneal exudate was incubated with PBE for 1 h, followed by exposure to arachidonic acid (AA) and generation of reactive oxygen species (ROS) was measured by flow cytometry using 2',7'-dichlorodihydrofluorescein diacetate. Results: PBE in a dose dependent manner significantly reduced acetic acid induced writhing response in mice (P < 0.001). In peritoneal exudates, PBE significantly inhibited AA induced generation of ROS, P < 0.01. Conclusions: The present study indicates that PBE has promising analgesic activity, worthy of future pharmacological consideration

Oral doxycycline with topical tacrolimus for treatment of stasis dermatitis due to chronic venous insufficiency: A pilot study

Objectives: Chronic venous insufficiency (CVI) in lower limbs manifest as stasis dermatitis. The anti-collagenase, anti-inflammatory and immunomodulatory effects of doxycycline and the T-cell inhibitory effects of tacrolimus could theoretically modify the disease pathophysiology. This study was undertaken to evaluate the efficacy and safety of four weeks combination therapy of oral doxycycline 100 mg with topical tacrolimus 0.1% for stasis dermatitis associated with CVI. Materials and Methods: A single-arm, interventional pilot study was conducted on subjects with CVI of C4 to C6 category (CEAP classification: clinical, etiology, anatomical, pathophysiology). Treatment duration was four weeks with fortnightly follow-ups. Primary efficacy was assessed as changes from baseline of pigmentation, erythema, edema, itching and hair loss of the affected area evaluated on Likert scale scores. Secondary efficacy parameters were percentage improvement of the dermatitis area and changes in ulcer dimensions (maximum length and breadth), if present. Safety evaluation included all treatment emergent clinical signs and symptoms reported by the patients and/or observed by the physician. Results: Out of 19 recruited subjects, 15 completed the study for analysis. Significant (P<0.01) improvement in pain, edema, pigmentation, erythema and exudation were observed. Reduction of ulcer dimensions was also statistically significant (P<0.01). 86.6% showed improvement of the dermatitis area, 6.7% patients failed to show any improvement and 6.7% showed worsening. Adverse effects were observed in only two subjects. Conclusion: This pilot study suggests efficacy of this combination therapy in controlling features of stasis dermatitis but further studies are needed for validation