Læknablaðið : fylgirit - 01.05.1978, Qupperneq 67

Halldór Steinsen
When naproxen first. came on the market here
in Iceland in March 1974 its metabolism and
clinical effects were known to a certain extent.
I have, however, not seen any reports on its
effects on the metabolism or excretion of
tryptophan.
The patient who caused this investigation to
be initiated was a 52 years old woman with arthrit-
is rheumatoides, angina pectoris and moderate
hypertension.
She began to take naproxen on February 2nd,
1975, 750 mg daily. At about the same time
she began to experience periods of sweating,
reddening of the face, tachycardia and intestinal
irritability. These symptoms usually occurred
shortly after meals, at which time she had also
taken her drug. There was no diarrhea, headache
or asthma sensation.
She reduced the naproxen dose herself to 125
mg x 2-3 daily and felt the above mentioned
symptoms eased but did not disappear. In the
autumn of 1975 she felt the symptoms get worse
again and complained of this during a follow-up
examination. As these symptoms were remini-
scent of those found in carcinoid syndrome, her
urine was again tested for 5-hydroxyindole. The
test was positive on two occasions. Quantitative
examination revealed a daily excretion of 38.7 mg
hydroxyindole/g creatinine.
Tests for careinoid tumour were negative.
Therefore it was investigated whether the
increased hydroxyindole excretion was in any way
related to the drugs being administered to the
patient. .
This investigation did not appear to rule out
the possibility that the increased 5-hydroxyindole
excretion might be somehow related to the
naproxen intake. It was therefore considered to
be of relevance to see if other patients on
naproxen reacted in a similar manner. Alto-
gether the urine of 30 patients was tested, 8
men and 22 women, including the first. Most
of them were in-patients at the Department of
Medicine at the St. Josephs Hospital. A few
were outpatients. No selection was made as to
age, sexj disease or other drugs. They had
POSITIVE TESTS FOR 5-HIAA
AFTER NAPROXEN INTAKE
been taking naproxen from four days to several
months. The results are as follows.
H.
To see if the size of the naproxen dose had
any influence on the amount of 5-hydroxyindole
in the urine I have plotted the amount of 5-
hydroxyindole excreted in mg/g creatinine versus
the daily dose of napraxen in mg. Quite clearly
most of the patients had taken 750 mg per day,
but since 10 of these gave a negative test and
the 15 giving a positive test showed a great
variation in the amount excreted, from less than
10 to 52.67 mg hydroxyindole per day, these
measurements do not indicate that the dosage
alone governs the amount of 5-hydroxyindole in
the urine.
m.
As mentioned earlier, the tests were done on
patients who were being treated with naproxen
in the department at a particular time. The
average age is therefore high or 66.06 years,
excluding the one 10 year old. 'Wie average age
for the women is higher than for the men or
70.28 years vs. 59.18 years. The positive
individuals were found to be older. The average
age for women was 71.07 years and for men
64.33 years. The average age for the negative
ones was 61.83 years for women and 56 years
for men. However, the age spread was rather
large; the youngest positive woman was 52 years
old; the oldest negative one was 86 years old.
Therefore I cannot suggest any influence of age
on the basis of this data. The same is true for
the distribution according to sex. The fílct that
relatively fewer men than women excrete 5-
hydroxyindole is not significant as the men are
too few and also younger.
IV.
As regards the indication for naproxen treat-
ment it is clear that there are more osteoarthrit-
is and spondylarthritis patients in the positive
group, but this does not appear to be signifi-
cant. The same is true for the secondary
diagnoses, as shown here.
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