Thanks for writing in.
will not cause side effects in long run even if it is been used for 4 years. Because over 4 years , drug has been taken only during periods and 2-3 tablets.
The possible side effects are--
nausea, diarrhea, allergic rashes, asthma aggravation,dizziness
, allergic rashes, insomnia, vertigo, dizziness, fluid retention and some more.
Some of the dangerous side effects are hemolytic anemia
and aplastic anemia
One may get one or more of the above side effects or none at all.
So taking drug only during periods - 2 to 3 tablets is unlikely to cause side effects. You can use it for pain relief , it is safe.
I hope I have answered your query.