Blood platelets symptoms and conditions

my 95 yr. old mother was given 2 SMZ/TMP pills 12 hrs apart and within hours after the 2nd one, spiked a fever and became flush around her eyes and then her entire face. She ended up in the emergency room. Several days later she broke out with hives, red blotches, arm bruises, a skin infection, and blood vessel breaks on her arms and legs. She also itched terrible all over. Doctors thought it was her blood platelets causing this but they were wrong. She is allergic to sulfur drugs. Finally after 5 weeks now she seems to be improving. This is a very dangerous drug for some.

Some people have reported bruising as a side effect of Fosamax. Have these people talked to their doctors to see if bruising was an allergic type of reaction to Fosamax or if Fosamax had lowered their blood platelets leves which might have caused bruising. Does any one know if Fosamax lowers blood platelets levels?