Response to Rimiterol and Salbutamol Aerosols Administered by Intermittent Positive-pressure Ventilation

Abstract

SummaryThe bronchodilator and cardiac effects produced by aerosols of 0G5% salbutamol and 0(5% and 1% rimiterol administered for three minutes in 40% oxygen by intermittent positivepressure ventilation (I.P.P.V.) were compared in 15 asthmatic patients. Salbutamol and both the concentrations of rimiterol were equipotent in peak bronchodilator effect, but salbutamol had a significantly longer duration of bronchodilator action. There was significantly less increase in heart rate after rimiterol than after salbutamoL Aerosols of 0-5% rimiterol, 0 5% salbutamol, and saline were administered by I.P.P.V. to 10 normal volunteers. There was no difference between the mean heart rates after 0 5% rimiterol and saline but a highly significant increase in mean heart rate was observed after 05% salbutamol. It was concluded that 0(5% rimiterol was an effective short-acting bronchodilator drug with little or no cardiac beta1-adrenergic activity when administered for three minutes by I.P.P.V. in 40% oxygen.

Comparison of the beta2‐adrenoceptor selectivity of rimiterol, salbutamol and isoprenaline by the intravenous route in man.

“…Muscular tremor is a commonly reported, undesirable effect of oral 12-adrenoceptor stimulating drugs (Kennedy & Simpson, 1969;Freedman, 1971; Legge et al, 1971;Schumann & Herxheimer, 1971), however, few quantitative determinations have been made. Cooke et al (1974) also reported the frequent occurrence of tremor after salbutamol given by intermittent positive-pressure ventilation. By both these routes, higher plasma levels of the drugs are achieved initially, than when given by pressurized aerosol and are responsible for such effects (Walker, Evans, Richards & Paterson, 1972;.…”

“…In normal subjects the 12-selectivity of rimiterol by aerosol has been confirmed (Griffin & Turner, 1971;Phillips et al, 1971). Cooke et al (1974) recently compared salbutamol and rimiterol in equipotent bronchodilating doses by intermittent positive-pressure ventilation in asthmatic and normal subjects, and found that salbutamol produced greater and more prolonged tachycardia.…”

“…The drug has several properties which make it potentially useful in the treatment of severe asthma by the parenteral route. In vitro and in vivo animal and human studies have demonstrated rimiterol to be an effective bronchodilator with a high degree of 02 -adrenoceptor selectivity, coupled with a relatively short half-life (Carney, Daly, Lightowler & Pickering, 1971; Griffin & Turner, 1971;Laity, 1971;Prime, Kamburoff & Gunthner, 1971;Bowman & Rodger, 1972;Kamburoff, Griffin & Bianco, 1972;Phillips, Woolnough, Marinova & Turner, 1972;Svedmyr, Malmberg & Thiringer, 1972;Evans, Paterson, Shenfield, Thomas & Walker, 1973;Griffin, Williams & Maughan, 1973;Cooke, Kerr, Willey, Hoare, Grant & Crompton, 1974).…”

The acute effects of the administration of rimiterol aerosol in asthmatic children.

“…Thus both rimiterol and orciprenaline showed bronchodilator selectivity when used as aerosols in children, even though orciprenaline has been shown to be less,f2-selective than rimiterol in pharmacological studies (O'Donnell & Wanstall, 1974 Grant & Crompton, 1974) or in inhalation therapy using, for example, a Wright's nebulizer, the short duration of action of rimiterol may be an additional safety factor in that, if it should be necessary to withdraw therapy, the effects of the drug would be more readily reversed. A similar situation would apply to the use of this drug by the intravenous route.…”

Comparative potencies and beta2‐adrenoreceptor selectivities of rimiterol and salbutamol aerosols.

“…Studies in man have demonstrated rimiterol to be an effective short-acting bronchodilator by the inhalational and parenteral routes of administration, with a high degree of 12 -adrenoceptor selectivity (Griffin & Turner, 1971; Prime, Kamburoff & Gunthner, 1971; Phillips, Woolnough, Marinova & Turner, 1972; Svedmyr, Malmberg & Thiringer, 1972;Griffin, Williams & Maughan, 1973; Shenfield & Paterson, 1973;Cooke, Kerr, Willey, Hoare, Grant & Crompton, 1974;Evans, Shenfield, Thomas, Walker & Paterson, 1974;Bianco, Kamburoff & Prime, 1975; Marlin & Turner, 1975a, b & c Figure 1. The % FEV1 increases from control after all the doses of the drugs were significantly greater than those after placebo (P < 0.01).…”