Will pain killers increase creatinine level in blood?

Question

My brother used pain killer injuctions 1 month back,
Still Creatinine level in blood is 1.8
This happend due to Pain killers or malfunction of a kidney?

Answer 1

Creatinine levels can be elevated due to malfunction of the kidneys.
This can also occur in muscular young to middle aged people due to muscle mass.
It can also be a side effect of some medications, what was the pain killer involved?