How do diuretics work?
You are probably familiar with at least a few diuretics. Beer is well known to tend to make people urinate more than they would if they drank a similar volume of water. The problem is that you may need to take a diuretic for a long time. You need something that doesn't harm your kidneys significantly! And you can probably think of reasons that beer would be a poor choice.
One class of diuretic drugs works by blocking the kidney's ability to absorb sodium again. The kidneys regulate the content of dissolved material in your blood (its osmotic properties) and they respond to this reduced sodium by putting more water in the urine, maintaining a balance.
The other big class of diuretics blocks the reabsorption of water in the kidney, so again more water is excreted. In both cases, much of the extra fluid gets pumped out, your heart pumps more easily, and your blood pressure drops somewhat. Within each of these categories, there are additional classifications. Different drugs act in different parts of the kidney and in different ways.
The category of drugs called loop diuretics (because they act within the Loop of Henle, a crucial part of the kidney). The Loop of Henle can rapidly cause a person to excrete a lot of sodium and water. Three examples used a lot in HCM are furosemide (Lasix), bumetanide (Bumex), and torsemide (Demadex). These drugs are used frequently for heart failure. Thiazide diuretics are probably not used as often in HCM. They are especially useful for treating hypertension. Potassium-sparing diuretics (including Spironolactone) decrease fluid levels in the body without causing the loss of potassium. However, potassium-sparing diuretics are not as effective at reducing blood pressure as the other types.
Effects of diuretics
You may have already guessed a key effect: you will urinate a lot more while taking a diuretic. It sometimes takes a bit of time to get used to this. One general piece of advice: make sure you take the last daily pill of diuretic a number of hours (say, 6 or 8) before you go to bed - or you will have to get out of bed at least once during the night! The number of daily doses, time between doses, and length of time you need to take diuretics will depend on which one you are taking as well as your condition.
Make sure you tell your doctor about other medications, supplements, vitamins, or herbs that you are taking. Some of them can interact with particular diuretics.
The most commonly prescribed diuretic for HCM is Furosemide (Lasix), a loop diuretic. If you have been prescribed diuretics by your doctor, it is advised to weigh yourself each day at the same time (first thing in the morning is advised). If your weight increases by 2 or more pounds, then it is usually advisable to continue to take the diuretic. Be sure to discuss this with your doctor if you do not see this weight gain. You may be told that you do not need to take diuretics each day (an every other day schedule may be advised). It is also imperative to maintain an appropriate blood potassium level when taking diuretics. Your doctor may prescribe potassium supplements, depending on the drug and the length of time they expect you to take the drug.
Side effects of diuretics include frequent urination, extreme fatigue, muscle cramps, thirst, loss of appetite, nausea, vomiting, dizziness, confusion, restlessness, blurred vision, or dehydration. Serious side effects include allergic reaction to the diuretic, irregular heartbeat, or kidney failure.
This list sounds bad! But millions of people take these drugs every day, and few of them have any of these problems. The important thing is for you to take the drugs as prescribed, take a supplement if prescribed, and pay attention to your body if you start developing symptoms. After you've paid attention, call your doctor! They may prescribe other medications to decrease side effects. They might change your drug or dosage. You should not stop taking your diuretic without consulting your doctor first.