Phentolamine mesylate (OraVerse), a nonselective a-adrenergic blocking drug, is the first therapeutic agent marketed for the reversal of soft-tissue anaesthesia and the associated functional deficits resulting from an intraoral submucosal injection of a local anaesthetic containing a vasoconstrictor. In clinical trials, phentolamine injected in doses of 0.2 to 0.8 mg (0.5 to 2 cartridges), as d...

The relative roles of prostaglandins and the sympathetic nervous system in mediating the hypotensive effects of hydralazine were studied in awake dogs with and without pretreatment with indomethacin, propranolol, and phentolamine. In normal dogs, mean aortic pressure decreased 23 +/- 4 mm Hg after administration of hydralazine (cumulative dose of 0.8 mg/kg). This hypotensive effect of hydralazi...

Background: Lisdexamfetamine is a stimulant used for the treatment of attention-deficit/hyperactivity disorder. Limited data exist regarding the presentation and management of patients with lisdexamfetamine toxicity. Case Presentation: A 17-year-old female with history of prior suicide attempt presented to the emergency department after ingestion of 50 lisdexamfetamine 40 mg capsules which belo...

The role of the sympathetic nervous system in the renal vasoconstriction induced by sodium restriction has been assessed in normal man in balance on a 10-mEq sodium intake. Renal blood flow was measured with radioxenon injected into the renal artery. Phentolamine infused into the renal artery at rates of up to 3 mg/min did not increase net renal perfusion or alter its intrarenal pattern. That d...

A 9-year-old girl accidentally injected her right thumb with an adult dose of epinephrine through an auto-injector syringe, delivering 0.3 mg of 1:1000 epinephrine. This injection caused immediate ischemic changes in the digit. This is the first reported case of accidental self injection by a child of an adult dose of epinephrine and its successful treatment with low-dose phentolamine simultane...

1. The aim of the investigation was to determine whether the adrenoceptors of the chick rectum preparation complied with Ahlquist's classification; phentolamine (0.1 mug/ml) and propranolol (0.05 mug/ml) were used as specific antagonists of alpha- and beta-adrenoceptors, respectively.2. Propranolol antagonized phenylephrine, isoprenaline and noradrenaline in the chick rectum preparation, althou...

Phentolamine was administered orally to 21 patients with persistent ventricular premature contractwons. In I5 patients the ventricular premature contractions were abolished, while in 5 a conspicuous decrease in their frequency was observed. The effective dose of phentolamine was either 50 or 75 mg. administered 4 times a day in all but 2 of the patients. The maximum antiarrhythmic effect was se...