Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Emergency care is appropriate for heavy bleeding, exposed bone, or a toe that appears to have lost its blood supply.
Request prompt medical assessment for a blister, crack, or open sore that is not improving.
Do this sooner if you have diabetes, poor circulation, reduced sensation, or a weakened immune system.
Seek urgent medical help if the toe or foot develops spreading redness, increasing warmth, pus, fever, or rapidly worsening swelling.
These can be signs of infection.
A cold, pale, blue, or black toe needs urgent assessment, particularly if the change is new or accompanied by severe pain or numbness.
These signs may indicate severely reduced blood flow.
A toe that becomes suddenly bent after an injury, especially with marked swelling, an open wound, or inability to bear weight, also needs prompt assessment.
Arrange a routine appointment if the toe is painful, rubs in your shoes, becomes increasingly stiff, or affects walking.
You should also seek advice if you repeatedly develop corns or calluses, or if footwear changes are not enough.
Every sign above is quoted from the sofidex article on Mallet toes. If you are not sure, err upward — it is always reasonable to be checked.