“Ever heard of Liquorice?
How about मुलेठी? यष्टिमधु? ज्येष्ठमध??”
Well they are all different names of the same herb. Botanical name is Glycyrrhiza Glabra. And the part of this herb that has historically been used around the world and across the cultures is “it’s Root”.
Liquorice literally means “Sweet Root”, and यष्टिमधु also means “a sweet stick”. Liquorice root is known for it’s signature sweetness that is less intense but long lasting than sugar, hence the name. This sweetness comes from a chemical compound named Glycyrrhizin or Glycyrrhizinic Acid.
Glycyrrhizin is a saponin compound present in liquorice root. It is what gives liquorice the signature sweet taste. And you know what gives yashtimadhu it’s signature yellow color? It’s a glycoside named Isoliquiritin. Most of liquorice root’s medicinal properties can be traced back to one of these two compounds.
Not only in ancient Indian medicinal systems but also in Chinese and Egyptian medicine, liquorice is being used for treatment of various illnesses and their symptoms.
Cough and other Respiratory Diseases
I have personally seen many mummies and grandmas turning to yashtimadhu for treating their kid’s cough. Per Ayurveda, liquorice has expectorant properties, which means it helps clear our airways of mucus and can bring much needed relief from constant coughing. This effect of liquorice is much studied and well documented. 
Not just cough, liquorice has shown great promise in treatment of infections of respiratory tract. Glycyrrhizinic Acid from liquorice has shown to possess antibacterial activities against common respiratory offenders like bacteria causing Strep Throat (sore throat), bacteria causing pneumonia, and bacteria causing bronchitis, laryngitis etc. . Not only that water extract of liquorice is shown to have antiviral activity against Human Respiratory Syncytial Virus (HRSV), a virus responsible for causing lower respiratory tract diseases in infants and children. 
My mother in law’s tried and tested cough remedy is mixing 1/2 teaspoon yashtimadhu churna (liquorice root powder) with 1 tablespoon raw honey and giving the paste to the one that is coughing. She insists that you should not wash it down with water. Some people also add Sitopaladi Churna to the mix.
Gargling with yashtimadhu water has been shown to effectively combat sore throat in post operative patients. Gargling with liquorice water soothes sore throat because of it’s anti inflammatory properties. [4, 5]
Yashtimadhu is known to have anti-inflammatory properties which is why in traditional medicine it is used for the treatment of inflammatory diseases like arthritis, stomach ulcers, asthma etc. 
In Ayurveda and also in Chinese medicine, liquorice is considered to be a harmonising tonic that balances different humours in the body and helps keep us healthy. It is also said to have rejuvenative properties.
Ease up Menopause
Liquorice could be a great aid for women going through menopause and suffering from constant hot flashes as it is shown to reduce severity of recurrent hot flashes in menopausal women. 
Possible Adverse Effects of Liquorice Use
Liquorice intake can have some unwelcomed side effects like low potassium levels, water retention etc. But following are the major contraindications-
glycyrrhizin has been linked with premature delivery which is why refrain from taking liquorice during pregnancy. And if you must (for any other health reason) consult with your doctor first.
Liquorice induced hypermineralocorticoidism results in lowering potassium levels which can be detrimental for people with kidney and heart diseases.
Because liquorice is shown to reduce blood glucose levels, it should not be taken in conjunction with other blood sugar lowering diabetic medications.
Take Home Message
Liquorice/ Yashtimadhu is a potent anti-inflammatory, adaptogenic herb with a lot of medicinal properties and it sure can help with getting some relief from that persistent cough, but make sure to consult with your doctor before taking it.