Spironolactone is a specific pharmacologic antagonist of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule. Spironolactone causes increased amounts of sodium and water to be excreted, while potassium is retained. Spironolactone acts both as a diuretic and as an antihypertensive drug by this mechanism. It may be given alone or with other diuretic agents which act more proximally in the renal tubule. Aldosterone interacts with a cytoplasmic mineralocorticoid receptor to enhance the expression of the Na+, K+-ATPase and the Na+ channel involved in a Na+ K+ transport in the distal tubule . Spironolactone bind to this mineralcorticoid receptor, blocking the actions of aldosterone on gene expression. Aldosterone is a hormone; its primary function is to retain sodium and excrete potassium in the kidneys.
Spironolactone comes as a tablet and suspension (liquid; Carospir) to take by mouth. It usually is taken once or twice a day. Take spironolactone suspension consistently either with food or without food each time. Take spironolactone at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take spironolactone exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Shake the oral suspension well before each use to mix the medication evenly.
Your doctor may start you on a low dose of spironolactone and gradually increase your dose.
Spironolactone tablets and suspension release the medication differently in your body and cannot be substituted for one another. Only take the spironolactone product prescribed by your doctor and do not switch to a different spironolactone product unless your doctor says that you should.
Spironolactone controls high blood pressure, edema, heart
failure, and hyperaldosteronism but does not cure these conditions. It may take
about 2 weeks or longer before the full effect of spironolactone occurs.
Continue to take spironolactone even if you feel well. Do not stop taking
spironolactone without talking to your doctor.
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
Other side effects not listed may also occur in some
patients. If you notice any other effects, check with your healthcare
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
If you miss a dose of this medicine, take it as
soon as possible. However, if it is almost time for your next dose, skip the
missed dose and go back to your regular dosing schedule. Do not double doses.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Certain medicines should not be used at or around
the time of eating food or eating certain types of food since interactions may
occur. Using alcohol or tobacco with certain medicines may also cause
interactions to occur. Discuss with your healthcare professional the use of
your medicine with food, alcohol, or tobacco.
Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.
Remember that this medicine will not cure your high
blood pressure, but it does help control it. You must continue to take it as
directed if you expect to lower your blood pressure and keep it down. You may
have to take high blood pressure medicine for the rest of your life. If high
blood pressure is not treated, it can cause serious problems such as heart
failure, blood vessel disease, stroke, or kidney disease.
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of spironolactone in the pediatric population. Safety and efficacy have not been established.
No information is available on the relationship of age to the effects of spironolactone in geriatric patients.
Animal studies have shown an adverse effect and there are no adequate studies in pregnant women OR no animal studies have been conducted and there are no adequate studies in pregnant women.
Studies in women suggest that this medication poses minimal
risk to the infant when used during breastfeeding.