Try taking it without waiting for half an hour but together with the food instead.

"Conclusions: These results confirm that ziprasidone should be taken with food and that a meal equal to or greater than 500 kcal, irrespective of fat content, is required for optimal and reproducible bioavailability of the administered dose."
The impact of calories and fat content of meals on oral ziprasidone absorption: a randomized, open-label, crossover trial - PubMed