DBL Vinblastine Dosage/Direction for Use

DBL Vinblastine Injection is for intravenous use only. Fatal if given by any other route. Vinblastine should not be given intramuscularly, subcutaneously or intrathecally. In order to avoid the risk of extravasation, it is extremely important that the needle be properly positioned in the vein before the product is injected.
It is recommended that DBL Vinblastine Injection be administered ONCE EVERY 7 DAYS. Therapy is initiated in adults by the administration of a single intravenous dose of 3.7 mg/m² bsa (body surface area). Thereafter white blood cell counts should be made to determine the patient's sensitivity to vinblastine.
The recommended incremental approach to dosage at WEEKLY INTERVALS is as follows: (See table.)

Click on icon to see table/diagram/image

Dosage increase may be continued but must not exceed 18.5 mg/m² bsa for adults and 12.5 mg/m² bsa for children. Dosage should not be increased after the dose which reduces white cell count to approximately 3.0 x 10⁹/L (3000/mm³).
For most adult patients the dosage will be 5.5 to 7.4 mg/m² bsa. However, leukopenia can be produced at 3.7 mg/m² bsa; others may require 11.1 mg/m² bsa, and very rarely 18.5 mg/m² bsa.
A maintenance dosage is administered ONCE WEEKLY, one increment smaller than the dosage to produce the above degree of leukopenia. Hence, the patient is receiving the maximum dosage that does not cause leukopenia.
IT SHOULD BE EMPHASIZED THAT, EVEN THOUGH 7 DAYS HAVE ELAPSED, THE NEXT DOSE OF DBL VINBLASTINE INJECTION SHOULD NOT BE GIVEN UNTIL THE WHITE CELL COUNT HAS RETURNED TO AT LEAST 4.0 x 10⁹/L (4000/mm³). In some cases, oncolytic activity may be encountered before leukopenic effect. When this occurs, there is no need to increase the size of subsequent doses.
Maintenance therapy duration is dependent upon the disease being treated and the antineoplastic agent combination. Maintenance therapy for the treatment of Hodgkin's disease is subject to varying opinions as to duration. Prolonged chemotherapy for maintaining remissions involves several risks, among which are life-threatening infectious diseases, sterility and possibly the appearance of other cancers through suppression of immune surveillance.
Method of Administration: DBL Vinblastine Injection is a sterile solution of vinblastine sulfate in sodium chloride 0.9% injection.
The calculated dose of the solution may be infused via a flexible plastic container either directly into the vein or into the injection site of a running intravenous infusion.
Intravenous administration of DBL Vinblastine Injection may be completed in about one minute.
Care should be taken to avoid infiltration of subcutaneous tissues (see Warnings under Precautions).
DBL Vinblastine Injection may be further diluted with compatible solutions (0.9% saline or 5% glucose) for the purpose of IV infusion. However, dilution in large volumes of diluent (100 to 250 mL) or prolonged infusion, is not recommended, since this may cause irritation and increase the risk of extravasation. To avoid microbial contamination hazards, infusion should be commenced as soon as practicable after preparation of the mixture. Infusion should be completed within 24 hours of preparation of the solution and any residue discarded.
Diluted solutions which are not clear or show evidence of particulate matter should be discarded.
Caution is advised when injecting vinblastine into extremities. If the circulation is impaired, the risk of thrombosis is increased.