I also take 81mg of aspirin a day;
The possible adverse effects, are
Allergic reactions;skin rash,hives,nasal discharge(resembling hay fever)nasal polyps.
Stomach irritation,heartburn,nausea,vomiting,constipation,-infrequent to frequent.
Ringing in the ears (tinnitus) a sign of excessive doses or dose sensitivity-
Serious Adverse Effects; Acute anaphylactic reaction,allergic destruction of blood platelets and BRUISING.
Stevens-Johnson syndrome-
Hemorrhagic stroke in some populations.
Erosion of stomach lining, with silent bleeding- may be dose and frequency related.
Activation of peptic ulcer, with or without hemmorrhage-frequent with long term non-enteric-coated use.
Bone marrow depression,fatigue,weakness,fever,sore throat, abnormal bleeding or bruising.