Description

Dihydrotachysterol is a synthetic analog of vitamin D. It is considered as a reduction product of vitamin D2 (ergocalciferol). It stimulates bone mineralization as well as calcium and phosphorus absorption in intestine. Dihydrotachysterol has been used for the treatment of hypoparathyroidism, osteomalacia, osteoporosis, low calcium level, and kidney osteodystrophy. Though dihydrotachysterol is more expensive, dihydrotychysterol therapy is preferred as it has a more rapid onset of action (1-7 d) and a shorter time for dissipation of effect in the event of toxicity (2-3 weeks) than vitamin D2.

Pharmacodynamics

Dihydrotachysterol is hydroxylated in the liver to 25-hydroxydihydrotachysterol, which is the major circulating active form of the drug. It does not undergo further hydroxylation by the kidney and therefore is the analogue of 1,25-dihydroxyvitamin D. Dihydrotachysterol is effective in the elevation of serum calcium by stimulating intestinal calcium absorption and mobilizing bone calcium in the absence of parathyroid hormone and of functioning renal tissue. It also increases renal phosphate excretion. In contrast to parathyroid extract, dihydrotachysterol is active when taken orally, exerts a slow but persistent effect, and may be used for long periods without increasing the dosage or causing tolerance. Dihydrotachysterol is faster-acting than pharmacologic doses of vitamin D and is less persistent after cessation of treatment, thus decreasing the risk of accumulation and of hypercalcemia.

Indication

Used for the prevention and treatment of rickets or osteomalacia, and to manage hypocalcemia associated with hypoparathyroidism or pseudohypoparathyroidism. Also used for the treatment of vitamin D dependent rickets, rickets or osteomalacia secondary to long-term high dose anticonvulsant therapy, early renal osteodystrophy, osteoporosis (in conjunction with calcium), and hypophosphatemia associated with Fanconi syndrome (with treatment of acidosis).

Uses

1. Dihydrotachysterol is a form of vitamin D. Vitamin D is a fat-soluble vitamin and has properties of both vitamins and minerals. Vitamin D helps you to absorb calcium from what you eat. You need calcium to keep your bones strong, and to help your muscles and nerves work properly.
2. The term Vitamin D collectively refers to a group of structurally similar chemicals and their metabolites, which includes alfacalcidol (1 α hydroxycholecalciferol), calcitriol (1,25-dihydroxychole-calciferol), cholecalciferol (Vitamin D3), dihydrotachysterol(DHT) and ergocalciferol (Vitamin D2). These agents have antirachitic properties.
3. Dihydrotachysterol-2 (DHT-2) is a vitamin D2 analog for the Pharmaceutical industry.
4. Dihydrotachysterol-2 is used in the prevention and treatment of several bone growth disorders such as osteoporosis. Besides this the substance is also used to treat several abnormalities of the parathyroid glands such as hypoprathyroidism.

References

1. https://en.wikipedia.org/wiki/Dihydrotachysterol
2. https://www.drugbank.ca/drugs/DB01070
3. https://pubchem.ncbi.nlm.nih.gov
4. Jack Z. Yetiv and Joseph R. Bianchine, Hypertension, Cardiovascular Disease, Analgesics, and Endocrine Disorders, 1981, ISBN 0-12-788950-7
5. Carl P. Weiner and Kate Rope, The Complete Guide to Medications During Pregnancy and Breastfeeding, 2013, ISBN-10: 0312676468

Chemical Properties

White Solid

Originator

Hytakerol,Winthrop,US,1950

Uses

Calcium regulator. Preparation by reduction of Tachysterol. It is widely used for hypocalcemic hypoparathyroidism following surgical removal of parathyroids.

Definition

ChEBI: A hydroxy seco-steroid that is 9,10-secoergosta-5,7,22-triene substituted by a hydroxy group at position 3. A synthetic analogue of vitamin D that acts a bone density conservation agent.

Manufacturing Process

The process of isolating chemically uniform crystalline dihydrotachysterol comprises subjecting the solution of the crude hydrogenation product of tachysterol in benzine to chromatographic adsorption by means of active aluminum oxide while collecting the components having a minor tendency of being adsorbed, subjecting the said components to a repeated chromatographic adsorption and converting the components having a minor tendency of being adsorbed into its ester by treatment with acetic anhydride in pyridine solution, isolating the ester formed from the reaction mixture, subjecting its solution in benzine to chromatographic adsorption while collecting the components having a minor tendency of being adsorbed, recrystallizing these components, saponifying the crystalline ester and recrystallizing the dihydrotachysterol obtained.

brand name

Hytakerol (Sterling Winthrop).

Therapeutic Function

Blood calcium regulator

Veterinary Drugs and Treatments

DHT is used in small animals to treat hypocalcemia secondary to hypoparathyroidism or severe renal disease.

Purification Methods

Crystallise the sterol from 90% MeOH, UV: max at 242, 251 and 261nm (E1% 760, 1010 and 650) in EtOH. The acetate has m108-110o and [] +32.8o (CHCl3), UV: max at 242, 251 and 261nm (E 780, 910 and 600) in EtOH. The propionate has m 97-98o and [] +37o (CHCl3), UV: max 242, 251 and 261nm (E 750, 860 and 570) in EtOH. [Werder Hoppe Seyler's Z Physiol Chem 260 119 1939, Windaus et al. Justus Liebigs Ann Chem 499 1978 1932, Beilstein 6 III 2833, 6 IV 3994, 4161.]