Sodium Alginate + Magnesium Alginate can get in the way of how well ketoconazole is absorbed if the two are taken at the same time. To avoid this, keep a gap of about 2 hours between taking the alginate and taking ketoconazole. The same 2-hour gap is advised with a number of other medicines too, including tetracyclines, digoxin, fluoroquinolones, iron salts, neuroleptics, thyroid hormones, penicillamine, beta-blockers (atenolol, metoprolol, propranolol), glucocorticoids, chloroquine, bisphosphonates and estramustine.
These medicines are often taken together with some care. Your doctor may change a dose, space them apart or check on you more often. Make sure your doctor and pharmacist know you take both.