Nifedipine controlled-release tablets are a drug used to treat high blood pressure, and this drug must not be broken open and chewed when used, but must be taken whole with warm water, and is recommended for use every morning after meals. Some patients may see nifedipine controlled-release tablets in the stool, in fact, do not worry, the complete tablet has been absorbed by the body, the excretion is only the empty shell of nifedipine. The following precautions should be taken: 1. Gum enlargement may occur during medication, so it is necessary to keep the oral cavity clean and hygienic during the use of this drug. 2. Edema of the ankles may occur, so if this occurs, it is recommended that patients must eat a light diet and rest the edematous limb with a quilt or clothing.