Abstract
1. The urinary excretion of salbutamol and its sulphate metabolite was measured following oral (4 mg) and inhaled (4 x 100 micrograms) administration of salbutamol. 2. Total urinary recovery of salbutamol and its sulphate conjugate indicated a mean (s.d.) relative bioavailability of 92.2 (24.8) % following inhalation compared with oral administration. 3. The mean (s.d.) elimination half-lives of salbutamol and its sulphate conjugate were 5.7 (1.4) and 4.1 (2.1) h, respectively, after oral administration and following inhalation they were 6.1 (2.1) and 5.1 (1.0) h, respectively. 4. Following oral and inhaled administration it was found that in the first 30 min the mean (s.d.) percentage of the dose excreted in the urine as unchanged salbutamol was 0.18 (0.14) and 2.06 (0.80) %, respectively (P < 0.01). The drug content of a urine sample taken 30 min after inhalation is, therefore, considered to be representative of the amount of drug delivered to the lungs. It is proposed that this method can be used to evaluate the relative bioavailability of salbutamol to the lung following inhalation by different techniques and devices.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Borgström L., Nilsson M. A method for determination of the absolute pulmonary bioavailability of inhaled drugs: terbutaline. Pharm Res. 1990 Oct;7(10):1068–1070. doi: 10.1023/a:1015951402799. [DOI] [PubMed] [Google Scholar]
- Cullum V. A., Farmer J. B., Jack D., Levy G. P. Salbutamol: a new, selective beta-adrenoceptive receptor stimulant. Br J Pharmacol. 1969 Jan;35(1):141–151. doi: 10.1111/j.1476-5381.1969.tb07975.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Davies D. S. The fate of inhaled terbutaline. Eur J Respir Dis Suppl. 1984;134:141–147. [PubMed] [Google Scholar]
- Hetzel M. R., Clark T. J. Comparison of intravenous and aerosol salbutamol. Br Med J. 1976 Oct 16;2(6041):919–919. doi: 10.1136/bmj.2.6041.919. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Horn C. R., Essex E., Hill P., Cochrane G. M. Does urinary salbutamol reflect compliance with the aerosol regimen in patients with asthma? Respir Med. 1989 Jan;83(1):15–18. doi: 10.1016/s0954-6111(89)80054-x. [DOI] [PubMed] [Google Scholar]
- Jarvie D. R., Thompson A. M., Dyson E. H. Laboratory and clinical features of self-poisoning with salbutamol and terbutaline. Clin Chim Acta. 1987 Oct 15;168(3):313–322. doi: 10.1016/0009-8981(87)90007-6. [DOI] [PubMed] [Google Scholar]
- Lewis L. D., McLaren M., Essex E., Cochrane G. M. Plasma concentrations of salbutamol in acute severe asthmatics. Aust N Z J Med. 1990 Jun;20(3):204–207. doi: 10.1111/j.1445-5994.1990.tb01019.x. [DOI] [PubMed] [Google Scholar]
- Lipworth B. J., Clark R. A., Dhillon D. P., Moreland T. A., Struthers A. D., Clark G. A., McDevitt D. G. Pharmacokinetics, efficacy and adverse effects of sublingual salbutamol in patients with asthma. Eur J Clin Pharmacol. 1989;37(6):567–571. doi: 10.1007/BF00562546. [DOI] [PubMed] [Google Scholar]
- Morgan D. J., Paull J. D., Richmond B. H., Wilson-Evered E., Ziccone S. P. Pharmacokinetics of intravenous and oral salbutamol and its sulphate conjugate. Br J Clin Pharmacol. 1986 Nov;22(5):587–593. doi: 10.1111/j.1365-2125.1986.tb02939.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Newman S. P., Pavia D., Morén F., Sheahan N. F., Clarke S. W. Deposition of pressurised aerosols in the human respiratory tract. Thorax. 1981 Jan;36(1):52–55. doi: 10.1136/thx.36.1.52. [DOI] [PMC free article] [PubMed] [Google Scholar]