Læknablaðið : fylgirit - 01.05.1978, Page 47

SAUCYIATE SCRUM CONCENTRATION (MEAN2&Q)
pmol/l mg/100 ml
TME FlRST OAY OE ADMINISTRATION THE 10 1h OAV OF AOMINISTRATION
TIME (houf*) TlME(hours)
Fig. 2 Salicylate serum levels on the first and
1 Oth day of the test period.
200 mg/kg/day, the steady state in salicylate
serum levels were achieved on the 4th day from
the beginning of the test. The serum levels
were estimated daily at 8 o’clock a.m. and, on
the first, fifth and tenth day, the blood samples
were drawn more frequently, at two hours
intervals until 8 hours after the intake of the
medicine for to clarify the maximum serum
level reached during the test.
During the steady state, in the morning
samples, salicylate serum concentrations varied
between 10 and 20 mg/100 ml, which corres-
pond to 900 to 1400 umol/1.
The variations of the salicylate serum levels
on the first and lOth day are seen in detail in
Figure 2. During the steady state, the maxi-
mum of salicylate serum leVel were reached 8
hours after the intake of the medicine.
The half-life of salicylates in serum is known
to increase with increasing dosage. Correspon-
dingly, the time interval from the beginning of a
constant dosage of salicylates until the steady
state grows the longer the higher the daily dose
is.
In our earlier study with salicylates, we have
shown, that if the dosage of salicylates is about
100 mg/kg of body weight daily, the time interval
from the beginning to the steady state is between
6 and 7 days. The daily dosage of salicylates of
100 mg/kg of body weight was also demonstrated
to be too high, leading to salicylate intoxication
in about one third of the cases. The same
phenomenon was observed with different salicylate
preparations. In Figure 3, the test was done
with Bayer's Aspirin, and, in Figure 4 are
shown the similar results with the enteric coated
form of acetylsalicylic acid.
In the present study with benorylate, the serum
salicylate levels were lower than expected. In
the morning samples during the steady state the
serum salicylate levels were only between 10 and
20 mg/100 ml, which corresponds to 900 to 1400
umol/1. The serum levels did not reach the
values induced by sole salicylate administration
of 100 mg/kg of body weight daily. The lower
serurn levels may be due to incomplete absorption
(jmol/l mg/IOOml
Fig. 3.
Salicylate serum levels in
children treated with Asprin
"Bayer" the daily dosage being
about 100 mg/kg of body weight.
Days of treatment
45