Bsj. Van Toor et al., Systemic bioavailability of nasally applied chlorphenamine maleate (0.4% nasal spray) relative to tablets administered perorally, INT J CL PH, 39(4), 2001, pp. 173-178
Citations number
11
Categorie Soggetti
Pharmacology & Toxicology
Journal title
INTERNATIONAL JOURNAL OF CLINICAL PHARMACOLOGY AND THERAPEUTICS
Aim: This study investigated the bioavailability of single doses of 1.12 an
d 2.24 mg chlorphenamine maleate applied intranasally (0.4% nasal spray) re
lative to a single peroral dose of 8 mg chlorphenamine maleate (tablets). M
ethods: Twenty-four (24) subjects were treated with single nasal doses of 1
.12 mg and 2.24 mg chlorphenamine maleate (0.4% nasal spray) and two 4 ing
chlorphenamine maleate tablets (Piriton) on 3 separate study days according
to a 3-way cross-over design with a 7-day wash-out between periods. Blood
was sampled before and at 0.25, 0.50, 1.0, 2.0, 3.0, 4.0, 6.0, 8.0, 12, 16
and 24 hours after drug administration. Additional blood samples were obtai
ned 36, 48 and 72 hours after peroral administration only. All subjects wer
e included in the pharmacokinetic analysis. Results: Nasally applied chlorp
henamine maleate was readily absorbed, reaching peak plasma levels after 0.
25 to 3.0 hours. The dose-normalized estimated mean C-max values were 1.24,
1.43 and 1.21 ng/ml for the peroral tablet and the 1.12 ing and 2.24 mg na
sal dose, respectively. The dose-normalized estimated mean AUC(0-infinity)
values were 25.91, 26.44 and 25.56 ng x h/ml for the tablet and the 1.12 an
d 2.24 mg nasal dose, respectively. The estimated treatment ratios (nasal d
ose to tablet) of the dose-normalized values for the 1.12 ing nasal dose we
re 1.15 (90% CI: 1.0 - 1.32) and 1.02 (90% CI: 0.88 - 1.18) for C-max and A
UC(0-infinity), respectively, for the 2.24 mg nasal dose they were 0.98 (90
% CI: 0.85 - 1.13) and 0.99 (90% Cl: 0.85 - 1.13) for C-max and AUC(0-infin
ity) respectively. The other pharmacokinetic characteristics (t(max), t(1/2
), lambda (z), AUC((0-tf)), MRTtot, CL/f and V-z/f) were comparable across
all treatments. These data indicate that the disposition of chlorphenamine
maleate was independent of the route and dose of administration. Conclusion
s; Chlorphenamine maleate is readily absorbed after nasal application using
a 0.4% nasal spray. The nasal administration showed that the systemic bioa
vailability at the two dose levels used was comparable to that for the tabl
et. Maximum concentrations on the low dose, however, were higher and those
on the high dose were comparable to those for the tablet. The nasal applica
tion of chlorphenamine maleate does not alter the overall systemic exposure
compared to the oral route.