<p>Iron chelates with tetracycline. Since oral iron products interfere with absorption of oral tetracycline antibiotics, this product should not be taken within two hours of each other. Occasional gastrointestinal discomfort may be minimized by taking with meals. Absorption of iron may be impaired by concurrent administrations of penicillamine and antacid. In patients with renal failure, a risk of zinc accumulation may exist.</p>