Expert: Dr. Ravindra Bhaskar Ghooi - 6/28/2007

Question
hi:

my wife has been taking escitalopram (10mg) and
risperidone (0.75 mg) since the last one year.

she has not been getting her menstrual
periods since the last one year. eventhough her
doctor told her that this was due to risperidone,
we got her blood checked recently. it was found
that her blood sugar levels were elevated
(fasting sugar: ~190 mg/dl). our family physician
has now prescribed metformin (500 mg) twice
a day to control her sugar levels.

I have the following questions..
(i) how long does it take for the effect of metformin
to be noticed (stabilization of sugar levels)?
(ii) does she have to take an enhanced dose of metformin
because risperidone is also known to elevate sugar
levels?
(iii) would her taking metformin affect the beneficial
effects of escitalopram or risperidone?

thanks in advance,
tarak

Answer
Hi,
There are some things you have ommitted to inform me, such as what is your wife's age? and what was her menstrual history.
In so far as metformin is concerned, it should take effect within a week. Her dose of metformin will depend not on the risperidone or escitalopram but her sugar level. So if I can have more details, may be I can help more.
Ravi Ghooi