The vertiginous syndrome

Comparison of buccal and oral prochlorperazine in the treatment of dizziness associated with nausea and/or vomiting

The dizziness inherent in vertiginous disorders is often accompanied by nausea and/or vomiting. While prochlorperazine is effective in relieving nausea and vomiting, its low bioavailability following first pass metabolism in the liver and metabolism in the intestinal wall, compounded by the likelihood of regurgitation in the nauseous patient, may limit the therapeutic value of the oral preparation. A buccal preparation achieves higher plasma concentrations by direct absorption into the systemic circulation. In this randomised, double-blind, double-dummy trial in patients with vestibular disorders, in keeping with previous pharmacokinetic studies, buccal prochlorperazine achieved a significantly faster onset of effect compared with oral prochlorperazine (p = 0.04), and was significantly better in reducing the frequency of nausea (p = 0.02) and severity of vomiting (p = 0.05) at 24-36 hours. The frequency of vomiting was also reduced by buccal prochlorperazine compared with oral prochlorperazine, but this difference was only of borderline significance (p = 0.07). Buccal prochlorperazine was well tolerated and well rated by both patients and investigators, having no more adverse effects on the buccal mucosa than placebo and causing less drowsiness and sedation compared with the oral preparation. No advantages were reported for the oral preparation over buccal prochlorperazine. Buccal prochlorperazine is therefore safe and effective, and suitable for the treatment of dizziness associated with nausea and/or vomiting in patients suffering from vertiginous disorders.

The use of vestibular tests for the selection of anti-vertigo drugs

Vertigo is not a disease, but a symptom. Therefore, the therapy of vertigo is primarily directed at eliminating the underlying cause. In about half of the cases the cause will not become apparent, however, and the therapy is doomed to be symptomatic. Several types of drugs have been found to have an anti-vertigo activity, e.g. antihistamines, calcium antagonists, anti-emetics. For the selection of vestibular depressants, the vestibular caloric test and the rotation test can be used. The duration of the nystagmus induced by rotation is the most useful parameter. The lag-period, the extent and duration of the vestibular effects can be determined and compared with that of other substances. A stronger action on a nystagmus does not necessarily mean a stronger anti-vertiginous action. The final proof of an anti-vertiginous activity can only be established in clinical studies in patients with vertigo.

Vertigo. Current concepts in management

Vertigo is not a disease, but a symptom. The management of vertigo requires more than the treatment of the symptom alone, as it concerns the whole physical and psychological condition of the patient. In addition to causal treatment, symptomatic treatment is needed in many cases. This specific treatment consists of vestibular exercises and drug therapy. The efficacy and use of the different drugs available are discussed.