Drug information of Vasopressin

Mechanism of effect

Vasopressin acts on three different receptors, vasopressin receptor V1a (which initiates vasoconstriction, liver gluconeogenesis, platelet aggregation and release of factor VIII), vasopressin receptor V1b (which mediates corticotrophin secretion from the pituitary) and vasopressin receptor V2 which controls free water reabsorption in the renal medullar.

The binding of vasopressin to the V2 receptor activates adenylate cyclase which causes the release of aquaporin 2 channels into the cells lining the renal medullar duct. This allows water to be reabsorbed down an osmotic gradient so the urine is more concentrated.

Pharmacodynamic

Vasopressin is an antidiuretic hormone indicated for the prevention and treatment of postoperative abdominal distention, in abdominal roentgenography to dispel interfering gas shadows, and in diabetes insipidus.

 Vasopressin can cause contraction of smooth muscle of the gastrointestinal tract and of all parts of the vascular bed, especially the capillaries, small arterioles and venules. It has less effect on the smooth musculature of the large veins.

Vasopressin may also be used to control bleeding in some forms of von Willebrand disease and to treat extreme cases of bed wetting in children. It may also play a role in memory formation although the mechanism is unknown.

Pharmacokinetics

• Bioavailability: Destroyed by trypsin in GI tract; must be administered parenterally or intranasally
• Protein binding: 1%
• Onset (antidiuretic activity): IM/SC, 2-8 hr
• Onset (pressor activity) IV, 30-60 min
• Metabolism: Metabolized in liver and kidney; rapidly removed from plasma
• Half-life: 10-20 min (parenteral)
• Excretion: Urine (5-10%)

Drug indications

polyuria

Dosage

adult

Abdominal Distention

5 units IM initially; repeated q3-4hr PRN; may be increased to 10 units

Diabetes Insipidus

5-10 units IM/SC q8-12hr

Titrate dose on basis of serum sodium, serum osmolality, fluid balance, and urine output

Abdominal Roentgenography

10 units (0.5mL) IM/SC 2 hours before procedure, then 10 units IM 30 minutes before procedure

May give enema priotr to first dose of vasopressin

Pediatric

Abdominal Distention

Proportionately reduced adult dosage

Diabetes Insipidus

2.5-10 units IM/SC/intranasally q8-12hr

Continuous IV infusion: 0.0005 unit/kg/hr initially, then double dose q30min to reach desired effect; not to exceed 0.01 unit/kg/hr 

Titrate dose on basis of serum sodium, serum osmolality, fluid balance, and urine output

Drug contraindications

Hypersensitivity

Side effects

Diarrhea , nausea , vertigo , Tremor , sweating , allergic reactions

Interactions

dronedarone , Amiodarone , Papaverine , Pimozide , Thioridazine , Disopyramide , Sotalol , Grepafloxacin , Iloperidone , Ceritinib , Bepridil , Pasireotide , vemurafenib , Anagrelide , Lumefantrine / artemether , Arsenic trioxide , Efavirenz , Gatifloxacin , Halofantrine , Mesoridazine , Procainamide , Panobinostat , Ribociclib , Dofetilide , Ibutilide , Mifepristone , Dolasetron , vandetanib , Droperidol , Osimertinib , sparfloxacin , Clozapine , Toremifene , Quinidine , Ziprasidone , saquinavir , Ivabradine , Cisapride , Fingolimod , Methadone , Moxifloxacin , Nilotinib , Haloperidol

Alerts

• With gastrointestinal (GI) bleeding, infusion should be continued for 12-24 hours after bleeding has stopped, and dosage should then be tapered over 24-48 hours
• Continuous infusion should be administered via controlled infusion device
• Use caution in chronic nephritis with nitrogen retention
• Pre- and postoperative patients with polyuria
• Use caution in patients with seizure, migraine, asthma, heart failure, vascular disease, angina pectoris, coronary thrombosis, renal disease
• Use in pregnant women only when clearly needed

Points of recommendation

Vasopressin can cause temporary side effects such as nausea, stomach pain, or "blanching" of your skin (pale spots when you press on the skin).

Drinking 1 or 2 glasses of water each time you receive an injection may help ease these side effects. If you are receiving this medicine in your vein through an IV, you may be told not to drink water for a certain period of time.

While using vasopressin, you may need frequent blood tests. Your heart function may also need to be checked using an electrocardiograph or ECG (sometimes called an EKG).

Follow your doctor's instructions about the amount of liquids you should drink during your treatment with vasopressin. In some cases, drinking too much liquid can be as unsafe as not drinking enough.

Pregnancy level

C

Related drugs

Desmopressin