I use and suggest licorice (Glycyrrhiza glabra) especially for mood swings, PMS and hormonal fluctuations. I find it is often overlooked as a valuable tool for hormonal shifts. I also find many patients or clients tend to think of this as a candy, so the practitioner must educate them on proper ways to use licorice. Licorice is an adaptogen, a category of herbs used to support long-term endurance and help us adapt to stress. In herbal medicine, it is traditionally used for respiratory distress, especially deep wet coughs, and for digestive distress and it is a valuable tool for (PMS), premenstrual dysphoric disorder (PMDD), and perimenopause complaints.

Its effects on the endocrine system, hormonal balance, and mental health are often underestimated. In fact, licorice has potent bioactive compounds, including glycyrrhizin, glycyrrhetinic acid, and flavonoids that provide anti-inflammatory, adaptogenic, and neuroprotective properties that can ease the symptoms of hormonal shifts. 

Overview: Support for PMS and PMDD

Primarily, licorice acts as a hormonal mimic, a neurotransmitter supporter, and a cortisol modulator.

1. Hormonal Regulation. Licorice root can help balance estrogen and progesterone levels, acting as a mild phytoestrogen that mimics estrogen in the body when needed. It also modulates cortisol breakdown, reducing stress-related hormonal imbalances and easing common emotional symptoms such as irritability, anxiety, and mood swings.
2. Reduction of Inflammation and Pain. Licorice is anti-inflammatory, which means in the context of PMS that it can lower prostaglandin levels, which are often elevated during the menstrual cycle and contribute to cramps, headaches, and breast tenderness. Its ability to regulate cortisol also helps reduce inflammation and pain.

Because of these effects, women suffering the emotional distresses of instability, crying, depression, anger, anxiety and violent mood swings often feel more relaxed and less emotional.

How Licorice Affects the Endocrine and Hormonal System

Licorice interacts with the endocrine system primarily by regulating cortisol metabolism and mimicking estrogen. Its compound glycyrrhizin inhibits the enzyme 11β-HSD type 2, which is responsible for converting active cortisol into its inactive form. This leads to more sustained cortisol activity, supporting adrenal function in cases of fatigue and stress. However, while this effect can increase energy and resilience, excessive or long-term use may lead to elevated cortisol and therefore high blood pressure and fluid retention. (In fact, licorice tends to raise blood pressure in general; see below.)

But this herb doesn’t only affect cortisol. Licorice also acts like estrogen. It modulates estrogen-sensitive pathways and potentially stabilizes hormonal fluctuations. This makes it especially beneficial for addressing low estrogen states, such as in the luteal phase of the menstrual cycle or during perimenopause.

Support for Brain and Mental Health

Though I have not seen articles identifying licorice as an MAOI (monoamine oxidase inhibitor), it appears to act like it, enhancing serotonin levels that improve mood and ease anxiety. Its flavonoids have shown neuroprotective action, shielding brain cells from oxidative damage and inflammation.

Through these actions, licorice appears to help women maintain resilience under stress, especially during hormonal fluctuations. This is a core adaptogenic trait, whereby adaptogens help us ease feelings of burnout, fatigue, and associated cognitive impairments as well as mild depression.

Licorice Contraindications and Risks

As with most powerful herbs, these numerous benefits often come with strong cautions. Like St. John’s wort, licorice has a long list of contraindications. However, unlike St. John’s wort which changes the metabolism of pharmaceuticals in the body, licorice often has a direct counter-effect on hormones and mineral balance.

Use it cautiously to avoid these potential side effects and contraindications:

1. Hypertension (High Blood Pressure) and Edema. Glycyrrhizin can cause fluid retention and can increase blood pressure by mimicking aldosterone, a hormone that regulates salt and water balance. Those with hypertension, heart disease, or kidney disorders should avoid licorice. Deglycyrrhizinated licorice (DGL) is a process which removes glycyrrhizin and it may be a safer option for these individuals, however results may be mixed or weaker.
2. Hypokalemia. Long-term use (such as longer than 1-to-2 weeks) can deplete potassium levels, leading to muscle weakness and heart arrhythmias. Maintaining a healthy sodium-potassium balance is essential to proper nerve cell functioning in the brain.
3. Hormone-Sensitive Conditions. Licorice’s estrogen-like effects can make conditions such as breast cancer, uterine fibroids, or endometriosis worse. However, as a person with both fibroids and endometriosis, I can attest that occasional short-term use during acute periods of PMS have proven effective for me without side effects. When working with women with breast cancer, fibroids or endometriosis, work carefully with your health care team.
4. Drug Interactions. Like other potent herbs, licorice may interact with pharma meds in the body. Avoid licorice with patients who are on diuretics, corticosteroids, antihypertensive drugs, and antidepressants. Licorice can either amplify or reduce their effects.
5. Pregnancy and Lactation. Licorice is not recommended during pregnancy, as it may stimulate uterine contractions or affect fetal development. Avoid altogether with women at-risk for miscarriage; reassure women with healthy pregnancies that an accidental cup of tea with licorice will likely pose no harm. With breastfeeding, the estrogen effects of licorice are too strong (similar to red clover). Avoid altogether with breastfeeding.

Personal and Professional Observations: Licorice

In my 30+ years supporting women’s hormonal changes using herbs, I’ve observed the following:

• Small doses work best. Rather than a full dropper (25 drops or the typical ¼ teaspoon dose) of tincture, 5-10 drops or less often suffices for symptoms of PMS or PMDD.
• Both the tea and the tincture appear to work equally well.
• Long-term use should be discouraged in favor of short term (in the luteal phase, for instance) or targeted use such as a 2-week span.
• Because it is sweet and tasty, licorice can be hard for people to give up. Assure clients who wish to drink the tea long-term that their health will improve with small and intermittent doses, and that their compliance in limiting licorice will prove worthwhile.

Herbs to Combine with Licorice for Brain and Mental Health

Licorice pairs well for short-term PMS and PMDD support with other brain and mental health herbs including:

• St. John’s wort (Hypericum perforatum), especially with PMS, PMDD and mild depression
• Passionflower (Passiflora incarnata), especially with general brain and mental support
• Roses (Rosa rugosa), especially for PMS’s crying, breakdowns, grief, and feeling inconsolable
• Oats (Avena sativa), especially for micronutrient support and general emotional strength

Ideal Candidate for Licorice Use

Because it’s such a powerful herb, clinicians may be concerned about placing their patients onto a regimen that includes Glycyrrhiza, but using it properly and in the right situations can lead to positive outcomes.

The ideal licorice patient is someone who:

• Communicates clearly with the clinician and discloses all herbs he or she takes, and is trustworthy regarding full compliance
• Needs support for mild-to-moderate depression, mood swings, neuroinflammation, PMS, PMDD, perimenopause, anxiety, GAD
• Is of any age, though I discourage use in children younger than about 13
• Is not pregnant (or planning to get pregnant anytime soon) and is not breastfeeding
• Does not have high blood pressure
• Does not have kidney issues or complications
• Is not scheduled for surgery
• Is not taking any of the following drugs:
  • diuretics
  • corticosteroids
  • antihypertensive meds
  • antidepressants

When you’re working with this type of ideal client, you can readily integrate licorice into a safe and effective short-term protocol.

To learn more, enroll in the Herbs for the Brain: Nootropic, Herbal and Natural Support for Mental Health certificate course.

Nothing in this article is meant to serve as medical advice. These statements have not been evaluated by the FDA. This information is for educational purposes only and you are encouraged to work with your trusted health care team for health matters. This information is not intended to treat, diagnose, cure or prevent any disease.