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Leg swelling is not uncommon and has been experienced by many many people. Usually, this swelling is temporary and goes away after the underlying condition is healed.
Temporary Leg Swelling
This temporary leg swelling may be caused by an infection, burn or sunburn, insect bites, an injury to the leg such as a sprain, surgery, or even medications such a hormone drugs, steroids, blood pressure drugs. This may also be an part of the inflammatory response your body goes through it trying to protect and heal the leg from the cause of the trauma.
Long Term Leg Swelling.
Long term leg swelling is referred to as edema. This is usually related to specific medical conditions. These conditions may include diabetes, congestive heart failure, blood clot, varicose veins, kidney failure, liver failure or a number of cardio-vascular problems.
Treatment for this long term swelling is in conjunction with the treatment for the condition that caused it. Usually diuretics are also used to relieve the swelling or water-retention.
Permanent Leg Swelling
****In the situation of any permanent leg swelling whether the cause is known or unknown, the diagnoses of lymphedema must be considered****
There are several groups of people who experience leg swelling from known causes, but it doesn't go away or unknown causes where the swelling can actually get worse as time goes by.
This group includes those who have had the injuries, infections, insect bites, trauma to the leg, surgeries or reaction to a medication. When this swelling does not go away, and becomes permanent it is called secondary lymphedema.
Another extremely large group that experiences permanent leg swelling are cancer patients, people who are morbidly obese, or those with the condition called lepedema. What causes the swelling to remain permanent is that the lymph system has been so damaged that it can no longer operate normally in removing the body's waste fluid.
In cancer patients this is the result of either removal of the lymph nodes for cancer biopsy, radiation damage to the lymph system, or damage from tumor/cancer surgeries.
This is also referred to as secondary lymphedema.
Group three consists of people who have leg swelling from seemingly unknown reasons. There may be no injury, no cancer, no trauma, but for some reason the leg simply is swollen all the time.
The swelling may start at birth, it may begin at puberty, or may begin in the 3rd, 4th or even 5th decade of life or sometimes later.
This type of leg swelling is called primary lymphedema. It can be caused by a genetic defect, malformation or damage to the lymph system while in the womb or at birth or be part of another birth condition that also effects the lymph system.
This is an extremely serious medical condition that must be diagnosed early, and treated quickly so as to avoid painful, debilitating and even life threatening complications. Treatment should NOT include the use of diuretics.
I would see a doctor for your own safety
Abnormal buildup of fluid in the ankles, feet, and legs is called peripheral edema.
Swelling of the ankles - feet - legs; Ankle swelling; Foot swelling; Leg swelling; Edema - peripheral; Peripheral edema
Painless swelling of the feet and ankles is a common problem, particularly in older people. It may affect both legs and may include the calves or even the thighs. Because of the effect of gravity, swelling is particularly noticeable in these locations.
Foot, leg, and ankle swelling is common with the following situations:
Long airplane flights or automobile rides
Menstrual periods (for some women)
Pregnancy -- excessive swelling may be a sign of pre-eclampsia, a serious condition sometimes called toxemia, that includes high blood pressure and swelling
Injury or trauma to your ankle or foot
Swollen legs may be a sign of heart failure, kidney failure, or liver failure. In these conditions, there is too much fluid in the body.
Other conditions that can cause swelling to one or both legs include:
Venous insufficiency (when the veins in your legs are unable to adequately pump blood back to the heart)
Burns (including sunburn)
Insect bite or sting
Starvation or malnutrition
Surgery to your leg or foot
Certain medications may also cause your legs to swell:
Hormones like estrogen (in birth control pills or hormone replacement therapy) and testosterone
A group of blood pressure lowering drugs called calcium channel blockers (such as nifedipine, amlodipine, diltiazem, felodipine, and verapamil)
Antidepressants, including MAO inhibitors (such as phenelzine and tranylcypromine) and tricyclics (such as nortriptyline, desipramine, and amitriptyline)