There is no clear rule on how long it takes to sleep after taking nifedipine extended-release tablets, but it is recommended that you do not go to sleep immediately after taking them, but after half an hour or more. Nifedipine extended-release tablets generally work slowly in the body to maintain a therapeutically useful blood level for a longer period of time. If you go to bed immediately after taking the medicine and take a small amount of water, the drug may stay in the esophagus for a longer period of time, and the effect will be a little later, and should pay attention to the time of administration of the drug, in order to better maintain the blood concentration of the drug, strictly under the guidance of a doctor to use the drug reasonably. Nifedipine extended-release tablets may cause swelling of the feet and lower legs, as well as chest pain, nausea and other adverse reactions. People who are allergic to nifedipine are prohibited from taking this drug. Extended-release tablets should be swallowed without chewing, and if the dose needs to be adjusted under doctor’s supervision, it can be taken in half tablets along the center line of the drug. Specific medication should follow the doctor’s instructions.