Medically reviewed by Kristin Hall, FNP
Written by Our Editorial Team
Last updated 8/10/2022
When it comes to knowing how much medication to take, you typically read the side of the bottle, right? Winging it when it comes to prescription drug dosages isn’t exactly the brightest approach and can be dangerous, so people generally leave the dosing instructions up to their healthcare provider, and dutifully follow them.
When it comes to spironolactone, how much you take and how you take it depends a great deal on why you’re being prescribed the medication.
It’s used to treat a handful of conditions officially, and a few additional diagnoses “off-label” — and the dosing instructions vary depending on these uses.
Spironolactone is a potassium-sparing diuretic FDA-approved to treat a variety of conditions, including edema, heart failure, high blood pressure and an over abundance of the hormone aldosterone.
Off-label, spironolactone is often used to treat acne and excessive hair growth in women.
Your healthcare provider may prescribe a small dose of spironolactone when you first begin taking it, and increase that dosage with time.
Daily spironolactone doses tend to fall in the 50-150mg range.
Spironolactone is a prescription drug sold under the brand names Aldactone® and Carospir®. It is known as an aldosterone antagonist, which means it counteracts the effects of the hormone aldosterone in the body.
Aldosterone is created in the adrenal glands and is important in regulating sodium and potassium within the body.
The Food and Drug Administration has approved the use of spironolactone in the treatment of:
Certain types of heart failure
High blood pressure, in conjunction with other medications
Edema, or swelling caused by excess fluid
Hyperaldosteronism, or the over abundance of aldosterone within the body
As with many prescription drugs, there are also off-label uses of spironolactone. Off-label is a term used to describe uses of a prescription drug for which the FDA does not explicitly endorse.
Healthcare professionals may prescribe off-label use of a medication when they believe it’s appropriate for a patient and there is scientific literature backing it’s safety and effectiveness.
In the case of spironolactone, off-label uses include:
Hormonal acne and hair growth (hirsutism), specifically in women
Precocious puberty, or early puberty
Myasthenia gravis, a nerve disease
Male hormone blocking in transgender women
The dosing instructions of any prescription medication should come directly from the prescribing healthcare provider..
Understanding your current diagnoses and other medications you’re taking will help your healthcare provider determine the proper amount and timing of spironolactone doses.
Generally, spironolactone is taken by mouth once to twice a day, whether it’s taken as a tablet or a liquid formula, according to the National Institutes of Health.
Dosages of spironolactone are highly variable and depend on the specific condition for which it's being prescribed, as well as the individual patient.
Generally, daily spironolactone doses tend to fall in the 50-150mg range, although lower effective doses may be prescribed for certain conditions (eg, hypertension and congestive heart failure). The lowest dose you can be prescribed is spironolactone 25 mg.
Expect to work with your healthcare provider to find the right dosage for you and your condition. It’s common for healthcare providers to start at a lower dose of spironolactone and increase slowly, as needed.
While you don’t have to take the medication with food, you should take it consistently — so either with food or without it, every time. Also, in the name of consistency — take spironolactone at about the same time each day.
Tell your healthcare provider about all other medications, both prescription and over the counter, you’re taking before beginning spironolactone to avoid drug interactions. They can provide medical advice that will help lessen the risks involved in taking spironolactone with other drugs — but only if they know about them.
It may cause adverse events if taken with: potassium-increasing medications and potassium supplements, lithium, non-steroidal anti-inflammatory drugs (NSAIDs), cholestyramine, digoxin, certain antibiotics, certain narcotics, and more.
Because spironolactone influences androgens, or male hormones, men who take it may very well experience gynecomastia and difficulty with erections. Spironolactone’s drug maker reports nine percent of men taking an average 25mg dose will experience gynecomastia, and the risk increases with higher doses.
Other potential side effects include:
Stomach pains and cramps
Diarrhea and vomiting
Drowsiness and tiredness
Irregular menstruation and vaginal bleeding
Some adverse effects can be a sign of a serious or allergic reaction or even life threatening. If you experience the following, contact your healthcare provider right away: muscle weakness or cramps, pain in the upper right part of your stomach, tingling or pain in the extremities, yellowing of the eyes or skin, changes in heartbeat, confusion, inability to move your limbs, blood in stool or vomit, fainting, signs of dehydration, itching or hives, difficulty swallowing or breathing, flu-like symptoms, urinary disruption, appetite changes or unusual bleeding or bruising.