What is causing my feet to swell?

A woman with swollen legs. PHOTO/NET 

Although I am a nurse, I have failed to know the cause of my painless swollen feet. I went to a doctor who checked for anaemia, heart, kidney and liver diseases, leg blood circulation, blood pressure, and other general examinations which were normal. I had attributed the swelling to taking emergency pills but I stopped taking them sometime back. What could be the cause? Esther

Dear Esther,
Up to 60 per cent of the human adult body is made up of water with two thirds of the water being inside cells (intracellular) and a third being outside the cells including between cells (extracellular), in blood (plasma) and other body fluids.

When excess fluid (water or lymphatic fluid) is tapped in body tissues, swelling occurs and when we assume an erect posture as happens during day, the water accumulation will cause swelling of the feet (pedal oedema) but the swelling will almost be absent on waking up in the morning.

Oedema can result from eating food with too much salt, pregnancy, staying seated with legs folded for long hours, over-standing or walking long distances, heat, which causes loss of water from swollen blood vessels, medication including that for high blood pressure (amlodipine), and disease conditions including, liver, kidney and heart diseases, anaemia and venous circulation problems (varicose veins), among many others.

Women may get pedal oedema around the time of their period due to fluid retention related to monthly sex hormone changes. Taking emergency pills (especially since many abuse the pills by taking them many times in a month instead of only once) may also cause pedal oedema since they are composed of the female sex hormone progesterone.

It is unlikely that the pills cause your oedema. The fact that you get the oedema at home not at work could point to differences in both  environments with the office being cold because of an air conditioner and home being hotter, or what you do at the office (walking around) allowing proper blood circulation unlike sitting at home.  

Taking medication to remove excess fluid, reviewing medication for hypertension, getting a more serious method of family planning, and reducing the amount of salt in the food may relieve oedema. However, if the oedema is due to a disease condition, the disease itself requires added separate treatment before the oedema ceases.