Purpura toxicity.. Capillary damage may be directly due to certain toxins that cause toxic effects on the vascular wall

Purpura toxicity:
Capillary damage may be directly due to certain toxins that cause toxic effects on the vascular wall or because of an allergic reaction without any change in the number of platelets or shape.
Some medications such as antibiotics (chloramphenicol, sulfonamides) quinine carbromal and barbiturates may cause capillary damage.