There are essentially two types of Qust, Indian (Qust al Hindi) and Marine/Sea (Qust al Bahri). Both come in the form of a dried root and Qust has a praised high status in the aHadith which is on par with Hijama cupping.
Imam Ibn Qayyim Al Jawziyyah (rahimullah) said that both types of Qust provide considerable medicinal benefits. Qust is one of the remedies to always have at home which I must recommend to all my brothers and sisters who are serious about using Tibb an Nabawi to treat themselves and their loved ones.
Qust is hot and dry in the third degree and helps to dry out excess phlegm, help to remedy colds and influenza and nasal congestion. Imam Ibn Al Qayyim said that drinking an infusion of Qust helps strengthen the liver and helps to remedy weakness of digestion, slackness of the stomach, and if used as an ointment, it helps backache or rheumatic pain in the lumbar region.
Sea/Marine Qust is a little paler in colour and also milder in taste and more suitable for administering to children.
Imam Ibn Al Qayyim said that Qust is also very beneficial for illnesses relating to breathing and the chest – pleurisy (a type of painful infection of the lining of the lungs), asthma, heaviness in the chest (breathing difficulties) and it helps to reduce thirst. It also helps remove freckles, fade scars and helps to control skin discolouration on the face and the chest which results from pregnancy or malnutrition.
Galen noted that Qust can also help kill ringworm (intestinal parasites) and if applied as an ointment can remove dry scales which are shed by the skin, including dandruff.
In the Sunan, the Messenger of Allah (sallAllahu alayhi wassallam) praises the excellence of Qust as a general remedy and he is also reported mentioning it as a remedy for inflammation/infection of the throat as well as in another Hadith mentioning it with Hijama. Qust contains helicene and benzoic acid, both of which are substances that kill germs, hence the benefit in the treatment of infections and inflammations.
Reference to Hadith regarding the general excellence of Qust, and partnering it with Hijama in the same sentence.
Anas (radhi Allahu anhu) narrated that he was asked about the wages of the one who cups others. He said, “Allah’s Messenger (sallAllahu alayhi wassallam) was cupped by `Abd Taiba, to whom he gave two Sa of food and interceded for him with his masters who consequently reduced what they used to charge him daily. Then the Prophet (sallAllahu alayhi wassallam) said, “The best medicines you may treat yourselves with are cupping and sea incense.’ He added, “You should not torture your children by treating tonsillitis by pressing the tonsils or the palate with the finger, but use incense.”
Sahih Al Bukhari Vol. 7, Book 71, Hadith 599