PMDD after SSRIs or hormones: Why the brain may be the missing treatment target

Prepared for Femtech World by Dr Emilė Radytė, neuroscientist and co-founder and CEO of Samphire Neuroscience

The short answer

Premenstrual dysphoric disorder (PMDD) does not usually result from abnormal hormone levels.

Research suggests that the brain can respond differently to expected changes in estrogen, progesterone, and the progesterone metabolite allopregnanolone.

This helps explain why blood tests can look typical while a person’s experiences remain severe. It also gives researchers a clear reason to study nervous-system treatments alongside selective serotonin reuptake inhibitors (SSRIs), hormonal treatment, and psychological care.

Why can expected hormone changes cause severe PMDD experiences?

Hormones act as signals. They interact with receptors throughout the brain and influence networks involved in mood, stress, sleep, and emotional regulation.

Two people can have similar hormonal patterns and experience those signals in different ways.

Hantsoo and Epperson (2020) reviewed evidence that PMDD involves an altered response to changing levels of allopregnanolone, which modulates gamma-aminobutyric acid type A (GABA-A) receptors. GABA helps regulate neural activity and the stress response.

In PMDD, the issue may lie in the brain’s adaptation to allopregnanolone fluctuations across the menstrual cycle.

Experimental research supports this sensitivity model. Suppressing ovarian hormone fluctuations can reduce PMDD experiences in susceptible participants, while reintroducing physiologic concentrations can bring them back.

Researchers therefore describe PMDD as a disorder of sensitivity to hormonal change, while recognizing that no single pathway explains every case.

Do normal hormone test results rule out PMDD?

No. A blood test shows whether a hormone concentration falls within an expected range at one point in time.

It cannot show how a person’s brain responds to that signal across the cycle.

Clinicians diagnose PMDD by its timing and impact, using prospective daily ratings across menstrual cycles.

The American College of Obstetricians and Gynecologists (ACOG) recognises PMDD as part of a spectrum of premenstrual disorders and recommends an individualised, multimodal approach.

Which treatments have evidence for PMDD?

ACOG’s 2023 clinical practice guideline includes hormonal and nonhormonal medicines, psychological counseling, exercise, nutritional approaches, patient education, and surgery for selected cases.

SSRIs can work faster in PMDD than they often do in major depression. Hormonal approaches can suppress ovulation or stabilize fluctuations for some patients.

No treatment works for every person. Some patients do not improve, cannot tolerate side effects, have contraindications, or prefer another route.

When that happens, clinicians and researchers need to ask which part of the biological pathway still drives the condition.

Could brain stimulation treat PMDD?

Noninvasive brain stimulation offers a plausible research direction because it can influence neural networks involved in mood regulation.

Evidence from depression cannot establish that it works for PMDD.

Researchers need PMDD-specific randomised trials that measure experiences across the cycle and report safety, adherence, and clinically meaningful outcomes.

The distinction matters. A coherent mechanism creates a hypothesis. Only indication-specific clinical evidence can establish efficacy.

Key takeaways

• PMDD can occur with hormone levels that fall within expected ranges.
• Research points to altered brain sensitivity to hormonal change, including allopregnanolone fluctuations.
• SSRIs and hormonal approaches remain evidence-based options, often as part of multimodal care.
• Brain stimulation is a research target for PMDD, not a conclusion that can be borrowed from depression studies.

Learn more at https://www.samphireneuro.com/en-us/pmdd

Sources:

Hantsoo and Epperson (2020), Allopregnanolone in premenstrual dysphoric disorder.

American College of Obstetricians and Gynecologists (2023), Management of premenstrual disorders.