The vinca alkaloids are a class of medications that are used as injections or infusions to treat leukaemia, some lung cancers, advanced breast cancer (vinorelbine), blood disorders, Hodgkin’s disease and some other forms of cancer. They include vindesine, vinorelbine, vincristine and vinblastine. The active ingredients were originally derived from the Madagascan rosy periwinkle plant.
They must not be used in pregnancy unless the mother’s life is at risk as the foetus may be damaged. Adequate contraception must be used by all women during treatment. Breastfeeding must be ceased before use, but they may be used with caution in children.
Vinca alkaloids must be used with caution in nerve, muscle and lung disease, and not at all if suffering from a serious infection, nerve damage or thrombocytopenia (bleeding disorder due to low blood platelet count). Regular blood and marrow tests to check blood and marrow cells and liver function are essential.
Side effects are common and include the loss of all body hair, pins and needles sensation, nerve pain, muscle weakness, nausea and vomiting. Unusual effects include paralysis of some muscles, convulsions, constipation or diarrhoea, depression, headache, rash, fever and rarely unusual bleeding or bruising and yellow skin (jaundice) may occur.
Interactions are possible between vinca alkaloids and phenytoin, mitomycin, cisplatin and live virus vaccines (eg. Sabin polio). Alcohol should be avoided during treatment. An overdose is frequently fatal.
Despite significant side effects, these drugs may save the life of patients with leukaemia and other cancers.