Efficacy and Safety of Ambroxol Lozenges in the Treatment of Acute Uncomplicated Sore Throat

Abstract

Sore throat is the hallmark of acute pharyngitis. Although usually caused by viral infections, it is frequently treated with antibiotics. Such inappropriate use of antibiotics might best be challenged by offering efficacious and safe symptomatic pain relief instead. However, there is need for robust evidence to support such alternatives. Presently, the evidence from randomised, placebo-controlled, double-blind clinical trials (RCT) with the local anaesthetic ambroxol (CAS 23828-92-4) in the treatment of sore throat is being reviewed. This relates to five RCT in 1,772 patients; 1,713 were evaluable with regard to efficacy. Treatment with ambroxol lozenges was statistically significantly superior to placebo in reducing sore throat pain intensity with a high level of consistency of the estimated effect across the different studies. The effect had an early onset and lasted up to at least 3 h after a single first lozenge. The pain relief was associated with a statistically superior regression of pharyngeal redness and inflammation; with ambroxol, the overall efficacy was more frequently rated as at least "good". Treatment with the ambroxol lozenges was well tolerated. There was heterogeneity in reporting adverse events: in one later study with less severe baseline pain intensity there was more frequent reporting of hypoaesthesia of the oral cavity and tongue as an untoward phenomenon. In patients with more severe baseline pain this reflection of the medication's pharmacological action was only rarely reported as untoward. It is concluded that lozenges containing 20 mg ambroxol are a safe and efficacious treatment for acute uncomplicated sore throat of recent onset in adult patients.