PMDD is already a rollercoaster. But is it a hormonal coaster? Perhaps a histamine coaster? Or a wretched-ass combination of both. Here's the gist. For some people, histamine does seem to make PMDD worse, but antihistamines are not a proven PMDD treatment yet.

(the PMDD "histamine PMDD theory")

• Estrogen can make mast cells dump histamine. When estrogen levels go up (around ovulation and again right before your period) it can make your mast cells more active. Mast cells are like your body's tiny security guards. They hang out in your skin, lungs, and stomach, watching for "trouble." When they sense danger, they attack by releasing histamine (a chemical that helps fight off threats but can also cause:

• Anxiety or panic feelings
• Irritability or mood swings
• Restlessness or hyper energy
• Trouble sleeping or insomnia
• Racing thoughts or brain fog
• Feeling "wired but tired"
• Itching
• Stomach pain, bloating, or nausea
• Fast heart rate or palpitations
• Low blood pressure or feeling faint
• Swelling
• and more

• Histamine & estrogen create a mini spiral in your body. More estrogen leads to more histamine which leads to more estrogen. If you're already sensitive, this treacherous tango can feel like symptoms piling up. The estrogen side of this loop is worth understanding on its own — read What Is Estrogen Dominance and How Does It Connect to PMDD?

• Some PMDD symptoms are 'histamine-y': headaches, bloating, swelling, anxiety, nausea, brain fog, skin flares, even joint pain...these are all reported in people with mast-cell / histamine people too. Histamines are more than a runny nose.

• When your hormones swing, histamine swings, and that can amplify PMDD mood and body symptoms people with PMDD.

what histamine actually is

Histamine is an immune messenger. We need some to function, but too much, too fast or for those with issues processing histamine, it can cause problems to stack up fast.

histamine helps:

• allergic responses
• stomach acid
• blood flow
• injuries
• wakefulness
• ovulation/reproduction
  

can antihistamines help pmdd?

For many, they can. Here's what others have been trying.

classic allergy antihistamines (cetirizine, loratadine, fexofenadine)

nighttime/sedating ones (diphenhydramine)

H2 blockers like famotidine (Pepcid) that block a different histamine receptor.

But clinicians keep saying the same thing: this is mostly anecdotal, good stories, not big trials.

And while clinicians may not be on board just yet, thousands of people with PMDD have noticed an improvement in their lives when using antihistamines to help treat PMDD symptoms. Myself included. Everyone's different of course so make sure you talk to your doctor. If you happen to have a doctor that is fluent in medical gaslighting, get a second opinion.

I ultimately decided I didn't feel comfortable taking antihistamines so frequently and decided to dig deeper. It was then, that I accidentally found my root cause of PMDD. Today, I'm PMDD free, but everyone is different. Root causes are different. Treatments are different. But one thing remains, there is hope.

what the experts are saying right now

• Histamine/mast-cell activity can worsen PMS/PMDD in some people.

For more articles on PMDD, visit our PMDD Resources.