Praise be to Allaah.
Two scenarios may apply to having injections during the day
in Ramadaan:
1 – Where the injection
provides nourishment that takes the place of food and drink; this kind of
injection invalidates the fast because it is like eating and drinking.
2 – Where what is injected is not a kind of nourishment; this
does not break the fast or affect it. In this case it makes no difference
whether the injection is into a vein or a muscle.
But if it is possible to have these injections at night, that
is better and more on the safe side with regard to the fast.
Shaykh Ibn Baaz (15/257) was asked about the ruling on a
person who had intravenous and intramuscular injections during the day in
Ramadaan when he was fasting and completed his fast – was his fast
invalidated and does he have to make it up, or not?
He replied:
His fast is valid, because an injection into a vein is not
like eating or drinking; this applies more so in the case on an
intramuscular injection. But if he makes it up in order to be on the safe
side, that is better. If it can be delayed until nighttime, if he needs to
have it, that is better too, so as to avoid an area of scholarly dispute.
Shaykh Ibn ‘Uthaymeen was asked in Fataawa al-Siyaam
(p. 220) about the ruling on having injections into a vein, muscle or the
buttock.
He replied:
There is nothing wrong with having injections into a vein,
muscle or buttock, and that does not break the fast, because this is not one
of the things that break the fast; it is not food or drink, and it is not
like eating or drinking. We have already explained that this does not have
any effect on the fast. What does affect the fast is when a sick person is
given an injection of something that takes the place of food and drink.
The Standing Committee (10/252) was asked about the ruling on
administering medicine via injection during the day in Ramadaan, whether
that is nourishment or medication.
They replied: it
is permissible to administer medicine by needle into a muscle or vein to a
fasting person during the day in Ramadaan, but it is not permissible for the
fasting person to be given a nourishing injection during the day in
Ramadaan, because that comes under the ruling on eating or drinking, so that
injection is regarded as a means of breaking the fast in Ramadaan. If the
injection can be given into a muscle or vein at night, that is better.