Although it was first approved for the treatment of high blood pressure, spironolactone is readily used off-label to manage a variety of medical conditions including pattern hair loss, adult acne, hirsutism (excess body hair growth) and polycystic ovarian syndrome (PCOS). While spironolactone been shown to be effective in treating these conditions, there are possible risks and side effects that you should be aware of. Below, we’ll review common spironolactone side effects, whether there are differences between side effects for men and women and what to do if you think you might be experiencing side effects.
What is spironolactone?
Spironolactone is an aldosterone receptor antagonist and anti-androgen. Aldosterone receptor antagonists influence the balance of salt and water in the body (it’s why spironolactone is also referred to as a diuretic or water pill) while anti-androgens block the effects of male sex steroid hormones such as testosterone and dihydrotestosterone (DHT). These properties can be helpful in treating certain health conditions like high blood pressure and pattern hair loss.
What are the side effects of spironolactone?
Clinical studies on the safety of spironolactone show that side effects of this medication are typically mild and transient. Below is a list of commonly reported side effects of spironolactone. This is not a complete list. For more information on side effects, we encourage you to speak with your doctor and/or pharmacist.
Potential side effects of spironolactone include:
Spironolactone may cause an imbalance in electrolytes such as potassium, which can be serious. The medical term for this is hyperkalemia. It may be necessary for your doctor to monitor your electrolyte levels if you’re taking a high dose of spironolactone or using it long-term.
Dizziness or lightheadedness
Since spironolactone may cause blood pressure changes, some people may experience dizziness or lightheadedness, especially when changing positions (e.g., standing up from sitting or lying down). Some people may also experience palpitations, or an irregular heartbeat while taking spironolactone.
Breast tenderness and/or swelling
The anti-androgenic effects of spironolactone can lead to breast tenderness or swelling (gynecomastia).
Since spironolactone influences water retention, it can cause more frequent urination. This is typically more noticeable when first starting the medication and should subside over time.
In addition to the side effects listed above, spironolactone may also cause drowsiness, leg cramps or muscle spasms, as well as feminization in male patients. These changes may include a change in body fat distribution, reduction in facial and body hair and a reduction in sex drive (libido) (Angus et al., 2020). For this reason, male patients are typically offered an alternative anti-androgen treatment such as finasteride.
There have also been anecdotal reports of emotional side effects, weight gain and the development or worsening of depression and anxiety associated with spironolactone use. These side effects have not been formally studied, but we recommend speaking with your doctor if you notice changes in health status or mood while taking this medication.
Are there spironolactone side effects for women?
The anti-androgen effects of spironolactone can result in sex-specific side effects in women. One commonly reported side effect is menstrual cycle changes (e.g., irregular periods) (Patibandla et al., 2023). Female patients prescribed spironolactone to help with PCOS may find that spironolactone can actually help make periods more regular.
Women should not take spironolactone if they are trying to get pregnant, are pregnant or are breastfeeding. Spironolactone may cause developmental harm to a male fetus. Women who are of childbearing age but have no intention of becoming pregnant may still be prescribed spironolactone following a discussion of risks and benefits with their doctor and if appropriate contraception is used. Spironolactone may be safely taken at the same time as most oral contraceptive pills.
Are there long-term spironolactone side effects?
So far, available study data shows that patients can take spironolactone without serious or lasting side effects. That being said, bodies can respond differently to medications and it’s important to inform your doctor if you develop side effects or side effects do not improve. Your doctor will work with you to adjust the dosage of spironolactone as needed to help lower the risk of having an adverse reaction.
What happens if I stop taking spironolactone?
Studies have shown that the therapeutic benefits of spironolactone can continue for a while even after stopping the medication. However, you will need to consistently take spironolactone to maintain its effects in the long-term. Available data on the long-term use of spironolactone suggests that the medication is safe to use for extended periods of time.
If you’re prescribed spironolactone off-label to help treat pattern hair loss, it’s important to understand that hair loss will continue to progress if you come off the treatment. This is because pattern hair loss is a genetically determined condition. Spironolactone can help block the effects of DHT and lower androgen levels to stave off this process and allow hair to regrow, helping to improve the density and thickness of hair.
Spironolactone side effects: Takeaway
Spironolactone is an important tool in the management of various medical conditions. However, it should be used under the guidance of a doctor who can monitor for potential side effects and make necessary adjustments to ensure the medication's safety and efficacy. Spironolactone can cause side effects in male and female patients, but available literature and data suggest that these are usually manageable with proper medical guidance. Spironolactone remains an important treatment option for pattern hair loss, particularly for female patients. Consider starting a consultation today through XYON to connect with a doctor to see if spironolactone may be right for you.