Bioavailability of intramuscular ciclosporin in the pig.
We conducted a cross-over single-dose pharmacokinetic study in 4 pigs to measure the bioavailability of ciclosporin (CS) after intravenous and intramuscular administration. Each animal was given 5 mg/kg i.v. followed by 20 mg/kg i.m. after 1 week. Serial blood samples were taken over 36 h after each dose, and the concentration of CS was assayed by radioimmunologic methods. The pharmacokinetic parameters after intravenous administration were (mean +/- SD; n = 4): clearance = 327 +/- 21 ml/h/kg; volume of distribution = 7.2 +/- 2.8 liters/kg. The same parameters after intramuscular dosing were: clearance = 326 +/- 59 ml/h/kg; volume of distribution = 6.9 +/- 2.1 liters/kg. The percent bioavailability of intramuscular CS was 101.9 +/- 13.3 with a mean absorption time of 10.6 +/- 2.7 h. Our results indicate that following a single dose, the percent bioavailability of intramuscular CS in pigs is considerably greater than that reported in previous studies.
Filipponi
F
F
Istituto di Clinica Chirurgica Generale e Terapia Chirurgica, Università di Firenze, Italia.
Messori
A
A
Valenza
T
T
Fabbri
L P
LP
Falcini
F
F
D000818:Animals; D001682:Biological Availability; D003524:Cyclosporins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D007273:Injections, Intramuscular; D009994:Osmolar Concentration; D013552:Swine; D013997:Time Factors
D003524:Cyclosporins