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What are Loop Diuretics?

Dulce Corazon
Dulce Corazon

Diuretics are drugs that cause urination by slowing down the reabsorption of water and sodium, or salt, in the kidneys. There are different categories of diuretics and each of these act on different sections of the kidneys where reabsorption takes place. Loop diuretics act on the ascending loop of Henle, thus they are called loop diuretics. They generally inhibit the reabsorption of salt and water in these sections of the kidney, in order to limit the amount of salt and fluid circulating in the body. These substances are instead passed out of the body with urination.

These diuretics are usually used for two main purposes. One is to reduce hypertension, or high blood pressure, and the other is to decrease fluid accumulation associated with liver, kidney, and heart diseases. These drugs are more potent than thiazide diuretics, another type of diuretics, as they inhibit reabsorption of salt more effectively.

Diuretics slow down the reabsorption of water and sodium in the kidneys.
Diuretics slow down the reabsorption of water and sodium in the kidneys.

Kidney, liver, and heart disorders are conditions that can cause edema or fluid accumulation and swelling in various parts of the body. Edema is commonly seen in the hands and feet. When it affects the lungs, breathlessness often occurs. These conditions can all benefit from the use of loop diuretics.

The most common side effects of diuretics of this type are fluid and electrolyte imbalances, such as decreased levels of magnesium, potassium, and sodium in the body. Calcium levels are also often elevated. These electrolytes are substances that are often needed by cells to function properly. Patients with these imbalances usually present with confusion, irregular heart beats, and weakness. Other side effects include rashes, muscles cramps, and nausea.

Diuretics may be used to reduce high blood pressure.
Diuretics may be used to reduce high blood pressure.

During treatment, patients are advised to avoid sudden movements such as sitting or standing up from a lying position. This frequently results in an orthostatic hypotension, which is the sudden decrease of blood pressure due to the swift change in position. Patients with diabetes and gout should also inform their physicians about these problems as the use of these kinds of diuretics can aggravate their symptoms.

Diuretics may be used to decrease fluid accumulation in different areas of the body, including the lungs.
Diuretics may be used to decrease fluid accumulation in different areas of the body, including the lungs.

Nephrologists, doctors who specialize in the treatment of kidney diseases, and cardiologists, doctors who manage patients with congestive heart failure, are usually the ones prescribing diuretics for their patients. They usually instruct patients to take this medicine in the morning and not in the evening. This practice is mainly to prevent frequent trips to the bathroom to urinate during the night, which can disturb sleep. Some kinds of loop diuretics are also best taken with meals in order to prevent stomach upset.

Discussion Comments

Oceana

I took a loop diuretic for a short time to treat my hypertension. In addition to this, my ankles and feet had swollen up with fluid. So, the doctor said a diuretic would be the ideal treatment, at least until the excess fluid got out of my system.

Strangely, the diuretic made me sensitive to the sun. I thought this was an odd side effect. I turned pink after just twenty minutes outdoors, working in my flower garden.

So, I started covering every inch of my skin when I went outside. I even wore a hat and shades.

I'm glad that I only had to take the diuretic for a short period. I love being outside, and having to cover up like that in summertime would be very uncomfortable.

orangey03

I became very fatigued after starting my dose of loop diuretics, a side effect that my doctor warned me about. He also said that it would disappear as my body got used to the diuretic, and he was right.

The first five days, I felt like I had been tossed about in a stormy sea for days and spit ashore. I had no energy for daily tasks, and staying awake at work was a huge challenge.

By the sixth day, though, I started to feel normal again. I'm sure that all the flushing out was a shock to my system. I'm just glad the tiredness subsided, because I could not have lived like that for very long.

cloudel

@shell4life – I took a loop diuretic for a kidney condition, and I can't imagine what you must have gone through with all that thirst and no way to quench it. My doctor told me to be sure to drink enough fluids, so I washed my system totally out.

I suffered from low potassium as a result. My doctor said that loop diuretics can cause hypokalemia if you are not careful to eat plenty of potassium rich foods.

Honestly, I ate bananas and potatoes while on the diuretic, but I don't think that any amount of food could have counteracted all the flushing out that was going on. I needed to drink an insane amount of water, and it was like a raging river, carrying all my nutrients out with the toxins.

shell4life

The most bothersome loop diuretic side effect for me was the excessive thirst. My doctor put me on the diuretic to treat a heart condition, and because it was supposed to be getting rid of excess fluid, he didn't want me to introduce a bunch of new fluid by drinking too much water.

It was so hard to limit my fluid intake. I felt as thirsty just sitting there as I do when I have just done a ton of yard work in the hot sun. Sipping just did not satisfy me.

Since fluid-packed foods like ice cream and popsicles would count towards my fluid intake, I couldn't quench my thirst with those, either. I was so relieved when I got to stop taking the diuretic that I drank an entire case of water in one day!

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    • Diuretics slow down the reabsorption of water and sodium in the kidneys.
      By: maya2008
      Diuretics slow down the reabsorption of water and sodium in the kidneys.
    • Diuretics may be used to reduce high blood pressure.
      By: Photographee.eu
      Diuretics may be used to reduce high blood pressure.
    • Diuretics may be used to decrease fluid accumulation in different areas of the body, including the lungs.
      By: decade3d
      Diuretics may be used to decrease fluid accumulation in different areas of the body, including the lungs.
    • Loop diuretics act on the ascending loop of Henle.
      By: designua
      Loop diuretics act on the ascending loop of Henle.
    • Diuretics are usually prescribed to patients with kidney disease.
      By: joshya
      Diuretics are usually prescribed to patients with kidney disease.