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People experiencing severe discomfort before their periods are finding solace in a new TikTok trend.
This trend involves combining two over-the-counter medications: an allergy pill, such as Claritin or Zyrtec, and Pepcid AC, a heartburn remedy.
Despite sounding improbable, Terese Hansen from Omaha, Nebraska, decided to try this after enduring years of unexplained symptoms.
Hansen shared with NPR that she has suffered from persistent nausea, heartburn, and erratic body temperature for the past four years. These symptoms worsened around her period, leaving her feeling constantly on edge and exhausted.
“I could not be around anyone because I knew I was unpleasant,” she recounts.
Hansen was intrigued by TikTok videos of people using Pepcid AC and allergy pills, particularly those mentioning relief from premenstrual dysphoric disorder (PMDD), a condition marked by depression and anxiety due to hormonal changes before menstruation.
After consulting her doctor, Hansen decided to try this TikTok trend.
She described a remarkable change in her body, with improvements in her physical symptoms, energy levels, and mood.
“It was nuts,” she recalls. “My kids noticed, my boyfriend noticed. My boss noticed.”
The claim
Users on TikTok claim that combining allergy medication with Pepcid AC alleviates premenstrual symptoms, making them feel less irritable and more energetic. Some also report that this combination helps ease symptoms associated with perimenopause.
The evidence
No clinical trials have been conducted to test the safety or effectiveness of this TikTok trend.
“This is basically an evidence-free zone,” says Leigh A. Frame, executive director of the Office of Integrative Medicine & Health at George Washington University. “There’s no evidence that it does or doesn’t work.”
Nonetheless, experts consulted by NPR believe there’s a plausible biological reason why Hansen and others might benefit from this over-the-counter remedy.
The explanation involves histamine.
Histamine is released by the immune system when the body encounters an allergen, triggering an inflammatory response, which causes discomfort during an allergic reaction.
There’s some evidence that histamine levels also fluctuate with the menstrual cycle.
Estrogen, which promotes histamine release, varies throughout the month, while progesterone, acting as a natural antihistamine, decreases before menstruation.
During perimenopause, both hormones fluctuate rapidly and unpredictably.
These hormonal shifts can lead to mood changes and discomfort, explains Dr. Mara Rivera, a psychiatrist in Austin who specializes in mental health challenges related to the menstrual cycle and reproductive transitions.
Pepcid AC and allergy pills are both histamine blockers, acting on different receptors in the body. Although the relationship between hormones and histamine isn’t fully understood, Rivera suggests that these over-the-counter drugs might help manage histamine levels, mimicking the role of progesterone.
Histamine also affects neurotransmitter systems, including serotonin and dopamine. Anecdotally, Rivera notes that some of her patients experience mental health benefits when taking antihistamines for other conditions, like allergies.
Rivera views this trend as a modern example of how traditional remedies can hold some truth.
“Women have been doing this forever, just talking to one another, and seeing what works,” she says.
Dr. Tami Rowen, a gynecologist at the University of California, San Francisco, suggests that a placebo effect might be at play.
She points out that numerous studies show patients benefit from the placebo effect, regardless of a medication’s efficacy. This could be the case with these over-the-counter antihistamines, says Rowen, who agrees with Rivera that users likely experience genuine relief.
Rowen also notes that current treatments for perimenopause and PMDD are limited.
“As an academic researcher myself, it would be lovely if there was a way to study this,” she remarks.
A Band-Aid, not a solution
Frame emphasizes that there’s no clinical evidence supporting this over-the-counter hack, and worries that individuals using Pepcid AC and allergy medicine might not be addressing the root causes of their symptoms. Histamine is linked to various health issues, such as hormonal fluctuations, poor sleep, and thyroid problems.
“A healthy menstrual cycle should not be painful,” she states. “That’s a misrepresentation that we have been disserved by.”
The popularity of this trend highlights the need for more research into women’s health, she adds.
The bottom line
There is no data supporting the use of these drugs for PMDD or other medical conditions, but it might be reasonable to try them temporarily while waiting to consult a specialist, says Frame. She advises speaking with a doctor before taking any new medications.
While Pepcid AC and allergy medications are relatively low-risk, they are not without risks. Antihistamines can cause drowsiness, fatigue, dry mouth, gastrointestinal symptoms, and adverse drug interactions, particularly in older adults and those with kidney or liver issues.

