Terbutaline formulation

Several groups have investigated the effect of surfactants on emitted droplet size. In the early work performed by Polli et al., the surfactant sorbitan trioleate decreased the MM AD of the CFC dexamethasone suspension when added to the formulation (52). A suspension of terbutaline in a CFC system containing sorbitan trioleate surfactant was shown to have little change in emitted particle size when either 2.8 or 14mg/mL of surfactant was added (53). Interestingly, the surfactant had a significant effect on the obscuration (droplet concentration) of the laser diffraction instrument used to determine particle size. Surfactants may lead to an increase in MMAD due to decreased evaporation rates from aerosol droplets. This may occur because of their tendency to associate at the air liquid interface (54). 

Liu, P., Bergstrom, T., Clarke, F., Gonnella, N., and Good, W. Quantitative evaluation of aqueous isopropanol enhancement on skin flux of terbutaline (sulfate) I. Ion associations and species equilibria in the formulation. Pharm. Res. 9 1036-1042, 1992. 

R. M. Fielding, and R. M. Abra, Factors affecting the release rate of terbutaline from liposome formulations after intratracheal instillation in the guinea pig, Pharm. Res. 9 220 (1992). 

Ravishankar, H., Iyer-Chavan, I, Patil, P, Samel, A., and Renner, G. (2006), Clinical studies of terbutaline controlled-release formulation prepared using EUDRAMODE, Drug Deliv. Technol., 6, 50-56. 

Sharma P, Hamsa V. Formulation and evaluation of buccal mucoadhesive patches of terbutaline sulphate. STP Pharma Sci 2001 11 275-281. 

El-Gindy GA, Ali AS, El-Shinnawi OM. Preparation and formulation of sustained-release terbutaline sulphate microcapsules. Bull Pharm Sci Assiut XJniv 2000 23(1) 55-63. 

Terbutaline is a p2-selective bronchodilator that contains a resorcinol ring and thus is not a substrate for COMT. It is effective when taken orally, subcutaneously, or by inhalation. Effects are observed rapidly after inhalation or parenteral administration after inhalation, its action may persist for 3-6 hours. With oral administration, the onset of effect may be delayed for 1—2 hours. Terbutaline (brethine, others) is used for the long-term treatment of obstructive airway diseases and acute bronchospasm a parenteral formulation is used for the emergency treatment of status asthmaticus (see Chapter 27). 

In 7 healthy subjects pretreatment with oral theophylline for at least 4 days significantly increased the fall in serum potassium levels and rises in blood glucose, pulse rate, and systolic blood pressure caused by an infusion of terbutaline. A study in children given slow-release formulations of both theophylline and terbutaline found no increases in reported adverse effects and simple additive effects on the control of their asthma. ... 

Varshosaz J, Emami J, Jafari E. Comparison of hydrophilic natural gums and cellulosic polymers in formulation of sustained-release matrix tablets of terbutalin sulfate. Res Pharm Sci. 1 30-39, 2006. 

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