| Ticlopidine is restricted to patients with transient cerebral ischemia. Ticlopidine may be somewhat more effective than ASA in preventing fatal and non-fatal strokes. However, it is associated with neutropenia in 0.8-2.4% of patients, a serious side-effect which may be fatal. Patients on ticlopidine require blood tests every two weeks for the first three months of therapy. There have been more than 60 cases of ticlopidine associated thrombotic thrombocytopenic purpura (TTP) with 33% mortality rate. As well, there are other side-effects such as diarrhea that occurs in 12.5% of patients. Ticlopidine should be used only after careful consideration. The appropriate use of ticlopidine in the management of patients with cerebral ischemic events (TIA or stroke) is based on the following:
(a) Determining that the symptoms are due to focal cerebral ischemia, and differentiating the symptoms of dizziness due to vestibular dysfunction, lightheadedness, or syncope from antihypertensive drugs or cardiac dysfunction, and from symptoms due to migraine, epilepsy, hypoglycemia, or other causes, such as tumor.
(b) If investigation demonstrates that the events are caused by emboli from the heart, the patient should be treated with anticoagulants, such as warfarin.
(c) If the events are due to artery-to-artery emboli from the carotid bifurcation with a severe stenosis, the patient should probably be treated with ASA and offered carotid endarterectomy if medically suitable (70% to 99% stenosis).
(d) ASA should be the first line of defense for patients with TIA and threatened stroke, and after an initial stroke of any severity.
(e) The only drugs other than ASA that are available as platelet inhibitors and which have been shown to be of value for such patients are ticlopidine and clopidogrel.
(f) Before abandoning ASA in favour of ticlopidine, efforts should be made to improve the tolerability of ASA by reducing the dose, taking it with food, and using enteric coated ASA.
Ticlopidine will be reimbursed for patients: |