VASOPRESSIN
Note: Vasopressin tannate is no longer commercially available in the USA.
Chemistry - A hypothalamic hormone stored in the posterior pituitary, vasopressin is a 9-aminoacid polypeptide with a disulfide bond. In most mammals (including dogs and humans), the naturalhormone is arginine vasopressin, while in swine the arginine is replaced with lysine. Lysinevasopressin has only about 1/2 the antidiuretic activity of arginine vasopressin. The commerciallyavailable vasopressin products may be a combination of arginine or lysine vasopressin derived fromnatural sources or synthetically prepared. The products are standardized by their pressor activity inrats [USP Posterior Pituitary (pressor) Units]; their antidiuretic activity can be variable.
Commercially available vasopressin has little, if any, oxytocic activity at usual doses.
Vasopressin injection occurs as a clear, colorless or practically colorless liquid with a faint, characteristic odor. Vasopressin is soluble in water.
Vasopressin may also be known as antidiuretic hormone, ADH, 8-arginine-vasopressin or betahypophamine.
If the aqueous injection is to be administered as an intravenous or intra-arterial infusion, it may bediluted in either D5W or normal saline. For infusion use in humans, it is usually diluted to aconcentration of 0.1 - 1 Unit/ml.
At doses above those necessary for antidiuretic activity, vasopressin can cause smooth musclecontraction. Capillaries and small arterioles are most affected, with resultant decreased blood flow toseveral systems. Hepatic flow may actually be increased, however.
Vasopressin can cause contraction of smooth muscle of the bladder and gall bladder and can increase intestinal peristalsis, particularly of the colon. Vasopressin may also decrease gastric secretions and increase GI sphincter pressure. Gastric acid concentration remains unchanged.
Vasopressin possess minimal oxytocic effects, but at large doses may stimulate uterine contraction. Vasopressin also causes the release of corticotropin, growth hormone and follicle-stimulatinghormone (FSH).
Uses, Indications - Vasopressin is used in veterinary medicine as a diagnostic agent and in thetreatment of diabetes insipidus in small animals.
In human medicine, vasopressin has also been used to treat acute GI hemorrhage, stimulate GIperistalsis. Prior to radiographic procedures it has been used to dispel interfering gas shadows or tohelp concentrate contrast media.
Vasopressin is distributed throughout the extracellular fluid. The hormone apparently is not boundto plasma proteins.
Vasopressin is rapidly destroyed by the liver and kidneys. The plasma half-life has been reportedto be only 10-20 minutes in humans.
Contraindications/Precautions - In humans, vasopressin is contraindicated in patients withchronic nephritis until nitrogen retention is resolved to reasonable levels. It is also contraindicated inpatients who are hypersensitive to it.
Because of its effects on other systems, particularly at high doses, vasopressin should be usedwith caution in patients with vascular disease, seizure disorders, heart failure or asthma.
Although the drug has minimal effects on uterine contractions at usual doses, it should be usedwith caution in pregnant animals.
Overdosage - Overdosage can lead to water intoxication. Early symptoms can include listlessnessor depression. More severe intoxication symptoms can include coma, seizures and eventually death.
Treatment for mild intoxication is stopping vasopressin therapy and restricting water access untilresolved. Severe intoxication may require the use of osmotic diuretics (mannitol, urea or dextrose)with or without furosemide.
The following drugs may potentiate the effects of vasopressin: chlorpropamide, urea, carbamazepine, and fludrocortisone.
Chemistry - A hypothalamic hormone stored in the posterior pituitary, vasopressin is a 9-aminoacid polypeptide with a disulfide bond. In most mammals (including dogs and humans), the naturalhormone is arginine vasopressin, while in swine the arginine is replaced with lysine. Lysinevasopressin has only about 1/2 the antidiuretic activity of arginine vasopressin. The commerciallyavailable vasopressin products may be a combination of arginine or lysine vasopressin derived fromnatural sources or synthetically prepared. The products are standardized by their pressor activity inrats [USP Posterior Pituitary (pressor) Units]; their antidiuretic activity can be variable.
Commercially available vasopressin has little, if any, oxytocic activity at usual doses.
Vasopressin injection occurs as a clear, colorless or practically colorless liquid with a faint, characteristic odor. Vasopressin is soluble in water.
Vasopressin may also be known as antidiuretic hormone, ADH, 8-arginine-vasopressin or betahypophamine.
Storage, Stability, Compatibility
Vasopressin (aqueous) injection should be stored at roomtemperature; avoid freezing.If the aqueous injection is to be administered as an intravenous or intra-arterial infusion, it may bediluted in either D5W or normal saline. For infusion use in humans, it is usually diluted to aconcentration of 0.1 - 1 Unit/ml.
Pharmacology - VASOPRESSIN
Vasopressin or antidiuretic hormone (ADH) promotes the renal reabsorption ofsolute-free water in the distal convoluted tubules and collecting duct. ADH increases cyclicadenosine monophosphate (cAMP) at the tubule which increases water permeability at the luminalsurface resulting in increased urine osmolality and decreased urine flow. Without vasopressin, urineflow can be increased up to 90% greater than normal.At doses above those necessary for antidiuretic activity, vasopressin can cause smooth musclecontraction. Capillaries and small arterioles are most affected, with resultant decreased blood flow toseveral systems. Hepatic flow may actually be increased, however.
Vasopressin can cause contraction of smooth muscle of the bladder and gall bladder and can increase intestinal peristalsis, particularly of the colon. Vasopressin may also decrease gastric secretions and increase GI sphincter pressure. Gastric acid concentration remains unchanged.
Vasopressin possess minimal oxytocic effects, but at large doses may stimulate uterine contraction. Vasopressin also causes the release of corticotropin, growth hormone and follicle-stimulatinghormone (FSH).
Uses, Indications - Vasopressin is used in veterinary medicine as a diagnostic agent and in thetreatment of diabetes insipidus in small animals.
In human medicine, vasopressin has also been used to treat acute GI hemorrhage, stimulate GIperistalsis. Prior to radiographic procedures it has been used to dispel interfering gas shadows or tohelp concentrate contrast media.
Pharmacokinetics - VASOPRESSIN
Vasopressin is destroyed in the GI prior to being absorbed and thereforemust be administered either intranasally or parenterally. After IM or SQ administration in dogs, aqueous vasopressin has antidiuretic activity for 2-8 hours.Vasopressin is distributed throughout the extracellular fluid. The hormone apparently is not boundto plasma proteins.
Vasopressin is rapidly destroyed by the liver and kidneys. The plasma half-life has been reportedto be only 10-20 minutes in humans.
Contraindications/Precautions - In humans, vasopressin is contraindicated in patients withchronic nephritis until nitrogen retention is resolved to reasonable levels. It is also contraindicated inpatients who are hypersensitive to it.
Because of its effects on other systems, particularly at high doses, vasopressin should be usedwith caution in patients with vascular disease, seizure disorders, heart failure or asthma.
Although the drug has minimal effects on uterine contractions at usual doses, it should be usedwith caution in pregnant animals.
Adverse Effects, Warnings
Adverse effects that can be seen include local irritation at the injection site (including sterile abscesses), skin reactions, abdominal pain, hematuria and, rarely, ahypersensitivity (urticarial) reaction. Overdosage can lead to water intoxication (see below).Overdosage - Overdosage can lead to water intoxication. Early symptoms can include listlessnessor depression. More severe intoxication symptoms can include coma, seizures and eventually death.
Treatment for mild intoxication is stopping vasopressin therapy and restricting water access untilresolved. Severe intoxication may require the use of osmotic diuretics (mannitol, urea or dextrose)with or without furosemide.
Drug Interactions
The following drugs may inhibit the activity of vasopressin: lithium, largedoses of epinephrine, demeclocycline, heparin, and alcohol.The following drugs may potentiate the effects of vasopressin: chlorpropamide, urea, carbamazepine, and fludrocortisone.