It is very uncertain whether oral iron changes serious adverse events compared with inactive control (very low certainty).
It is very uncertain whether oral iron sulphate changes serious adverse events ‐ active or inactive disease (14 days) compared with oral iron hydroxide polymaltose complex (very low certainty).
It is very uncertain whether parenteral iron changes serious adverse events compared with oral iron (very low certainty).
It is very uncertain whether IV iron sucrose changes serious adverse events ‐ mild to moderate disease (20 weeks) compared with oral iron sulphate (very low certainty).
It is very uncertain whether IV iron isomaltoside changes serious adverse events ‐ remission or mild disease (8 weeks) compared with oral iron sulphate (very low certainty).
It is very uncertain whether oral ferric maltol changes serious adverse events ‐ mild disease to quiescent (up to 52 weeks) compared with oral placebo (very low certainty).
It is very uncertain whether oral ferric maltol changes serious adverse events (12 weeks) compared with IV ferric carboxymaltose (very low certainty).
It is very uncertain whether IV ferric carboxymaltose changes serious adverse events ‐ mild to moderate disease (16 weeks) compared with oral iron sulphate (very low certainty).
The review found no eligible studies for this question.