Blood loss nifedipine

Kremens B, Brendel E, Bald M, Czyborra P, Michel MC. Loss of blood pressure control on withdrawal of fluconazole during nifedipine therapy. Br J Clin Pharmacol 1999 47(6) 707-8. 

Rapid lowering of the blood pressure with nifedipine, particularly sublingually, can precipitate cerebral ischemia, with confusion, loss of consciousness, and stroke. Cases of cortical blindness with macular sparing secondary to occipital lobe infarction have been reported (SEDA-17, 238). 

Transient cerebral ischemia, with aphasia and hemipar-esis in one patient and cerebellar dysfunction and loss of consciousness in another, has been observed with nifedipine (12). In addition, rapidly progressive hemiparesis, aphasia, and confusion, accompanied by a substantial fall in blood pressure, occurred in a patient whose hypertension (230/136 mmHg) was treated with sublingual nifedipine (13). Transient retinal ischemia, which may be recurrent, has also been attributed to nifedipine (14,15). Hypotension or cerebral steal are the likely mechanisms. 

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