Watermelon and grapes are fruits that act as natural diuretics, and celery, asparagus, artichoke, cucumber, eggplant and onion are vegetables that are natural diuretics. Herbal diuretics include dandelion, corn silk, ginger root, hawthorn, parsley, juniper berry and stinging nettle.
Pharmaceutical diuretics are available by prescription. There are several types, and each signals the kidneys to excrete more sodium from the body. Water binds to the sodium and is excreted, decreasing blood volume. The lower blood volume reduces the force necessary for blood circulation, thereby lowering blood pressure.
Diuretics eliminate excess fluids from the body by increasing the amount of urine excreted. They are sometimes recommended to treat high blood pressure, swelling, congestive heart failure, liver problems, kidney stones, glaucoma and lymphatic swelling. Some people turn to natural diuretics in an attempt to lose weight quickly; however, weight lost through excretion of fluids is temporary.
Because some essential minerals may be excreted along with the fluids, prolonged use of diuretics can lead to dehydration, kidney damage and an imbalance of electrolytes, which can cause heart failure and sudden death. Use of diuretics, both natural and pharmaceutical, should be supervised by a physician. Unwanted side effects of diuretics include headaches, dizziness, sleep issues, impotence, menstrual irregularities, excessive thirst, gout, and muscle weakness or cramping.