Product Information

Registration Status: Active

PROSULF INJECTION 1% is approved to be sold in Singapore with effective from 1989-02-10. It is marketed by MEDIPHARM PTE LTD, with the registration number of SIN03696P.

This product contains Protamine 1% in the form of INJECTION. It is approved for INTRAVENOUS use.

This product is manufactured by CP PHARMACEUTICALS LTD in UNITED KINGDOM.

It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.



Protamine sulfate is a drug that reverses the anticoagulant effects of heparin by binding to it. It was originally isolated from the sperm of salmon and other species of fish but is now produced primarily through recombinant biotechnology. Protamine sulfate was approved for medical use in the United States in 1969. Protamine sulfate (protamine (protamines) s) occurs as fine white or off-white amorphous or crystalline powder. It is sparingly soluble in water. The pH is between 6 and 7. The cationic hydrogenated protamine at a pH of 6.8 to 7.1 reacts with anionic heparin at a pH of 5.0 to 7.5 to form an inactive complex.


Protamine sulfate is usually administered to reverse the large dose of heparin administered during certain surgeries, especially heart surgery.

Mechanism of Action

It is a highly cationic peptide that binds to either heparin or low molecular weight heparin (LMWH) to form a stable ion pair, which does not have anticoagulant activity. The ionic complex is then removed and broken down by the reticuloendothelial system. In large doses, protamine sulfate may also have an independent—however weak—anticoagulant effect.


After IV adminsteration, protamine sulfate takes less than 5 min. to neutralize heparin.
12.3 L
Metabolic fate of the protamine-heparin complex has not been elucidated; however, protamine-heparin complex may be partially metabolized or attacked by fibrinolysin, freeing heparin.


Clearance is: 2.2 L/min


Administration of protamine sulfate intravenously could result in severe drop in blood pressure, dyspnea, bradycardia, pulmonary hypertension and anaphylaxis. Systemic hypertension, nausea, vomiting and lassitude were also reported. Overdosage of this drug may theoretically result in hemorrhage.

Active Ingredient/Synonyms

Protamine sulfate | Protamine sulfate |

Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.


  1. Health Science Authority of Singapore - Reclassified POM
  2. Drugbank