Short- and long-term effect of nifedipine on the visual field in patients with presumed vasospasm.

It is assumed that the ocular circulation may be involved in the vasospastic syndrome and patients with vasospasm have visual field defects that are neither ophthalmologically nor neurologically explainable. A retrospective study showed that 20 mg sustained-release nifedipine treatment given orally may be helpful in these cases. There was a marked short-term effect in cases with proven peripheral vasospasms but not in similar cases without such vasospasms. The study also showed that the effect could last for up to 12 months when 20 mg nifedipine was given twice daily but the long-term effect was slightly less than the short-term effect. A number of patients had to discontinue nifedipine treatment due to side-effects.