Vasopressin Pharmacology

Vasopressin

About Vasopressin
Posterior Pituitary Hormone,ADH Analog, Antidiuretic,in diabetes insipidus.
Mechanism of Action of Vasopressin
The drug exerts it`s antidiuretic action by acting through V1 and V2 receptors. The activation of V2 receptor present on basolateral side of cell membrane of collecting duct increases intracellular cyclic AMP formation; which leads to activation of cyclic AMP dependent protein kinase A and phosphorylation of relevant proteins. This phosphorylation promotes exocytosis of "aquaporin-2" water channels containing vesicles (WCVs) through apical membrane and more aqueous channels get inserted in to the apical membrane. Endocytosis and degradation of WCVs is also decreased. The water permeability of collecting duct cells increases in proportion to the population of aquaporin-2 channels in the apical membrane. Continuous V2 receptor stimulation also up regulates aquaporin-2 synthesis through cyclic AMP response element of gene encoding aquaporin-2. V2 receptor activation also increases urea permeability of terminal part of collecting duct by stimulating a vasopressin regulated urea transporter which increases medullary hyper tonicity. V1a receptor activation constricts vasa recta and reduce blood flow to inner medulla thus maintains high osmolarity in this region and contributes to antidiuresis. V1action also causes increased prostaglandin synthesis reduces response to V2 receptor stimulation and serves to control V2 effect highest drug levels.
It also directly constricts blood vessels through V1 receptors and controls bleeding.

Pharmacokinets of Vasopressin
Absorption: Administered intranasally or parenterally, Distribution: Distributed extracellularly, Metabolism: Peptide chain is rapidly cleaved enzymatically in liver, kidney, and other organs. Excretion: About 5% of drug is excreted unchanged in urine.
Onset of Action for Vasopressin
N/A
Duration of Action for Vasopressin
3 to 4 hours
Half Life of Vasopressin
25minutes
Side Effects of Vasopressin
1. Headache
2. Tremor
3. Vertigo
4. Angina
5. Vasoconstriction
6. Arrhythmias
7. Cardiac arrest
8. Myocardial ischaemia
9. Pallor
10. Decreased cardiac out put
11. Nausea
12. Vomiting
13. Flatulence
14. Abdominal cramps
15. Cutaneous gangrene
16. Water intoxication
17. Hypersensitivity reactions
18. Urticaria
19. Angioedema
20. Bronchoconstriction
21. Anaphylaxis

Contra-indications of Vasopressin
1. Hypersensitivity to the drug
2. Chronic nephritis
3. Coronary artery disease
4. Hypertension
5. Psychogenic polydipsia

Special Precautions while taking Vasopressin
1. Seizure
2. Migraine
3. Asthma
4. Cardiovascular disease
5. Renal impairment
6. Heart failure
7. Goiter
8. Fluid overload
8. In polyuric preoperative and postoperative patients

Pregnancy Related Information
Contraindicated
Old Age Related Information
Contraindicated
Breast Feeding Related Information
Contraindicated
Children Related Information
Use with caution
Neonates: Contraindicated
Indications for Vasopressin
1. Diabetes insipidus
2. Oesophageal variceal bleeding
3. Post operative abdominal distention

Interactions for Vasopressin
Carbamazepine: Antidiuretic effect potentiated
Typical Dosage for Vasopressin
I.M. or S.C.:
Diabetes insipidus: 5 to 20 units I.M. or S.C. injection. Repeat at every four hours.
Post operative abdominal distention: 5units I.M. Repeat at every 3 to 4 hours. Increase to 10units if required.
I.V.:
Oesophageal variceal bleeding: 20units over 15minutes.
Schedule of Vasopressin
H
Storage Requirements for Vasopressin
Store the injections at 2 to 8 degree C.Keep out of reach of children
Effects of Missed Dosage of Vasopressin
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose
Effects of Overdose of Vasopressin
Treatment includes water restriction and temporary withdrawal of Desmopressin until polyuria occurs. Severe water intoxication requires osmotic diuresis with Mannitol, dextrose, or urea (alone or with Furosemide)

Home Delivery for Vasopressin in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including vasopressin.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for vasopressin and other medicines and health products. Home delivery services for vasopressin may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take vasopressin only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for vasopressin before they complete the sale. You can get this information while placing the order for vasopressin with the pharmacy.

Vasopressin is a generic medicine name and there are several brands available for it. Some of the brands for vasopressin might be better known than vasopressin itself. If the pharmacy that's willing to deliver medicines to your home doesn't have vasopressin in stock, you can ask for one of the branded alternatives for vasopressin.