Swollen feet without pain may be physiological reasons, can also be caused by drug side effects or heart failure and other reasons. 1. Physiological reasons: if you stand for too long, suddenly walk too much, resulting in prolonged loading of the lower limbs, easy to make the lower limbs fatigue, lower limb venous blood return slower, especially some of the middle-aged and elderly people peripheral circulation function of the weakening of the feet can appear physiological swelling. 2. Drug side effects: when taking calcium ion blockers, such as nifedipine, felodipine or amlodipine and other drugs will trigger ankle edema, but there is no pain. Often the edema is significantly relieved when the medication is stopped. 3. Heart failure: When heart failure occurs, it will cause edema of the lower limbs, but without pain, which needs to be treated with diuretic under the guidance of the doctor, which can better relieve the condition. In addition, swollen feet may be related to some other causes. When there is foot swelling but no pain can first be observed, if the symptoms are more serious, you need to go to the hospital in time for examination, to find the specific cause for targeted treatment.