I had no clue about this

Antacid tablets, commonly used to relieve heartburn, contain calcium carbonate, which can be a quick and accessible source of calcium for tomato plants. When an antacid tablet is placed in the planting hole, it gradually dissolves, releasing calcium into the soil. This can help prevent blossom end rot by ensuring that the developing fruits have access to the calcium they need. It’s a simple and cost-effective method that many gardeners have found beneficial.