Gandhaka Rasayana is an Ayurvedic medicine in herbal powder or tablet form. It is used in the treatment of skin diseases, itching, chronic fever, urinary tract disorders etc
Gandhaka Rasayana  uses: 
It is used to treat chronic fever, skin diseases, diarrhoea, urinary tract disorders, pruritis, malabsorption syndrome, bleeding disorders, oligospermia.It is anti aging medicine, improves digestion, skin complexion and immunity.
Traditional indication:
Veeryakara – improves immunity, fertility and potency
Pushtikara – improves nourishment
Drudhadeha – improves body strength and stamina
Vahnikara – improves digestion strength
Prajakara – improves fertility in men and women
Kesha Krushnakara – Reileves grey hairs
Indicated in –
Dhatu Kshayaja Roga – diseases arising due to depleted body tissues – such as muscle wasting, tuberculosis, Irritable Bowel Syndrome, leading to severe weight loss etc.
Kandu – itching
Kushta – skin diseases
Shiro roga – diseases pertaining to head, headache
Visha – toxic conditions
For the treatment of above conditions, it is administered for a period of two months.
For the treatment of below conditions, it is administered for a period of six months.
Atisara – diarrhea, dysentery
Grahani – Malabsorption syndrome, Irritable Bowel Syndrome
Raktadosha – blood vitiation disorders such as abscess, bleeding disorders, vascular disorders etc
Hrutshoola – pain in cardiac region, gastritis
Jeernajwara – later stages of fever
Prameha – Urinary tract disorders, diabetes
Vatavyadhi – Neurological disorders such as paralysis, hemiplegia, neuropathy,  joint disorders etc
Koshtaroga – Intestine related disorders such as IBS, Ulcerative colitis
Gandhak Rasayan Dosage:
Traditional dose – 1 Masha – 1 gram
1 – 3 grams, once or twice a day before or after food or as directed by Ayurvedic doctor.
Dose based on age:
Children up to 5 years of age: not more than 250 mg per day.
5 – 12 years of age: 250 mg – 1 gram in divided doses per day.
Adults – 1 – 3 grams in divided doses per day.
How long to take?
This medicine can be safely taken for a period of upto 2- 6 months, based on your doctor’s advice.
Gandhak Rasayan  Side Effects:
Self medication with this medicine is strictly not recommended. Take this only under strict medical supervision.
Take this medicine in precise dose and for limited period of time, as advised by doctor.
Diabetic, hypertensive patients, cardiac patients, obese people, pregnant ladies, lactating mothers and children should take this medicine strictly under medical supervision.People with diabetes should check if the product contains sugar, before taking it.Keep out of reach and sight of children. Store in a dry cool place.
Gandhaka Rasayanam ingredients and how to make?
10 g fine powder of Gandhaka – Purified Sulphur
Godugdha – Cow milk
It is ground till dryness for 8 times each with the following.
Water decoction / juice extract of
Twak – Cinnamon – Cinnamomum zeylanicum
Ela – Cardamom – Elettaria cardamomum
Patra – Cinnamomum tamala
Nagakeshara – Mesua ferrea
Guduchi – Indian Tinospora (stem) – Tinospora cordifolia
Haritaki – Chebulic Myrobalan (fruit rind) – Terminalia chebula
Amalaki -Indian Gooseberry- Emblica officinalis / Phyllanthus emblica
Vibhitaki – Belliric Myrobalan – Terminalia bellirica
Shunti – Ginger (rhizome) – Zingiber officinalis
Bhringaraja – Eclipta alba
Ardraka – Ginger (rhizome) – Zingiber officinalis
Sita – Sugar Syru