The inexpensive drug could be a safe and effective alternative to antibiotics.
Even though acne is usually at its worst when we’re in our teens and twenties, it’s one of the most common skin conditions in adults, too. As many as one in three women have facial acne in their thirties, and an estimated one in seven continue to struggle with facial blemishes into their fifties.
Many experts recommend considering systemic therapies if topical medications aren’t working or if the acne is causing scars. But that usually means antibiotics, which can be less than ideal for a few reasons.
“Not only is antibiotic resistance a problem, but antibiotics can affect the gut microbiome with unwanted consequences,” says Abigail Waldman, MD, the clinical director of the Mohs and Dermatologic Surgery Center at Brigham and Women’s Hospital and a dermatologist at Mass General Brigham, both in Boston.
For women with a certain type of acne, one alternative has been an inexpensive drug used to treat high blood pressure called spironolactone. Used “off-label” for the skin condition, the drug blocks certain hormones that can cause acne. Men aren’t prescribed spironolactone for acne because of the side effects; men have developed breasts while taking the drug, according to the American Academy of Dermatology.
Largest Randomized Controlled Trial to Look at Spironolactone for Acne
Now results from the first large-scale clinical trial to look at the effectiveness of spironolactone in treating acne, published on May 16 in the British Medical Journal, add support for the inexpensive generic drug.
“Spironolactone has been gaining popularity [as a treatment for acne], and I think this randomized controlled trial with over 400 participants will help. The previous randomized controlled trials were with fewer than 40 women,” says Dr. Waldman, who was not involved in this study.
“Because spironolactone has been generic for many years, there is less financial incentive to conduct large, multicenter placebo-controlled trials in acne patients,” says Lindsay Strowd, MD, an associate professor of dermatology at Wake Forest University School of Medicine and a dermatologist at Atrium Health Wake Forest Baptist, both in Winston-Salem, North Carolina. Dr. Strowd was not involved in the new research.
After 3 Months of Treatment, Women Saw Significant Improvement in Their Acne
The UK study included 410 women older than 18, with an average age of 29, who had acne that had persisted for more than six months, and for whom oral antibiotics would have normally been the next treatment. Half were randomly selected to take spironolactone, while the other half were given a placebo.
For the first six weeks, the spironolactone group took 50 milligrams (mg) a day, and then the dose was increased to 100 mg per day until week 24.
The women were asked to complete questionnaires on their acne and quality of life relating to the condition at the start of the trial and then at 12 and 24 weeks into their treatment.
“The results showed that the women taking spironolactone saw a significant improvement in their acne after 12 and 24 weeks compared to those on the placebo,” said the lead author, Miriam Santer, PhD, a professor of primary care research at the University of Southampton in England, in a press release.
Spironolactone Could Offer an Alternative to Antibiotics for Many Women
“A significantly higher proportion of people also reported that they felt satisfied that their skin had been helped compared with those receiving placebo, and any side effects were uncommon and very minor. These results show that spironolactone could offer an alternative to antibiotics for many women with persistent acne to use alongside topical acne treatments,” she said.
“The findings also showed a significant objective reduction in acne at 24 weeks. This was a well-designed study, and I think it was reassuring that few side effects were noted, with headache being higher in the treatment group,” says Waldman.
What Kind of Acne Responds to Spironolactone?
Spironolactone is used for a very specific type of acne caused by hormonal imbalance in women, says Waldman. “This acne presents on the jawline, neck, and chest,” she says.
Usually, spironolactone is a second- or third-line treatment after topical medications such as benzoyl peroxide, topical retinoids, and oral antibiotics, says Waldman. “Often it is prescribed with an oral contraceptive, which increases its potency and prevents pregnancy complications while on the medication,” she says.
Spironolactone shouldn’t be used during pregnancy or if you’re trying to get pregnant because of its effect on hormones, and so women must be willing to use contraceptives while on the medication, she adds.
Antibiotic Resistance Is One of the Biggest Threats to Global Health
Spironolactone use for acne in the United States is very common, and its popularity has risen as dermatologists have become more conscious of antibiotic resistance. There has also been a push to minimize long-term use of oral antibiotics for acne treatment, says Strowd.
Antibiotic resistance happens when germs like bacteria or fungi no longer respond to the drugs designed to kill them, according to the World Health Organization (WHO).
Antibiotic resistance is one of the biggest threats to global health, food security, and development today, per the organization. Although there are many health situations where antibiotics must be used, it’s important to avoid using them unnecessarily, because it can contribute to antimicrobial resistance.