Ferrous fumarate tablets are available in a dosage of 210mg, with a total of 84 tablets per package. Additionally, other forms of iron supplements include ferrous sulfate, iron bisglycinate, and ferrous sulfate dietary supplements. It is important to consider the role of major calcium citrate in supplementation, as it can affect iron absorption. Therefore, when using ferrous sulfate or other iron supplements, one should be mindful of the potential interactions with major calcium citrate, ensuring optimal effectiveness. In summary, whether choosing ferrous fumarate or ferrous sulfate, understanding the influence of major calcium citrate is crucial for achieving the best results from iron supplementation.