What are cytotoxics?
Cytotoxic or immunosuppressive drugs suppress immune function.
They can suppress any arm of the immune system, like T cells
or B cells, they can suppress transplanted organ rejection, the
making of antibodies, or the attack of certain cells, viruses or
tumours. The use of cytotoxic drugs is called chemotherapy.
Cytotoxics kill or inhibit the action of the immune system. This
can result in death of cells or the interruption of the synthesis
of antibody. Certain cells of the immune system manufacture
antibodies, so if we turn off the manufacture of the antibodies,
the damage done to the body, as a result of immune complexes, ceases.
What cytotoxics are used to treat lupus?
Cyclophosphamide (Cytoxan) - best used intravenously.
Chlorambucil (Leukeran) - much better tolerated than oral Cytoxan,
long term use (more than 2 years) makes it a potent carcinogen.
Azathioprine (Imuran) - has modest effects on serious lupus, but
has the advantage of reducing steroid requirements.
Methotrexate (Rheumatrex) - works within weeks, & is taken
only once a week. Decreases joint inflammation, but can make
lupus patients more sensitive to ultraviolet light. Has little
effect on organ-threatening disease. Must be used carefully in patients
with kidney impairment.
What symptoms of lupus can cytotoxics be used to treat?
Cytotoxics are very strong drugs, & usually only used to treat
lupus when absolutely necessary. They are used on patients
who have major organ involvement, severe muscle inflammation, or
What are the side effects of cytotoxics?
Cyclophosphamide - hair loss, nausea, vomiting, possible infertility,
can result in the cessation of bone marrow function, resulting in
anaemia, & low levels of white blood cells & platelets.
Chlorambucil - occasional skin rashes, nausea, vomiting, diarrhoea,
bone marrow suppression(as with cyclophosphamide), increased production
of fibrous tissue in the lungs is a rare but serious problem.
Azathioprine - skin rashes, diarrhoea, nausea, vomiting(occasionally),
occasionally results in cessation of bone marrow function (as with
Methotrexate - nausea, vomiting, diarrhoea, anaemia, bone marrow
suppression(as with cyclophosphamide), liver damage.