Immunosuppressants and DMARDs Flashcards
Name common immunosuppressant ADRs
Myelosupression (leukopenia, anaemia and thrombocytopenia) and increased infection risk
Name 4 main immunosuppressant drugs/classes
Azathioprine, Cytotoxic Alkylating Agents, Calcineurin Inhibitors and Mycophenolate Mofetil
How does Azathioprine work?
Metabolises to 6-Mercaptropurine, which impairs DNA synthesis, killing dividing cells.
What gives azathioprine a high toxicity risk?
It’s metabolising enzyme (TPMT) is highly polymorphic in the population.
Name a cytotoxic alkyl imaging agent
Cyclophosphamide
How does cyclophosphamide work?
It is activated by CYP450 to form an Alkylating agent which forms DNA cross links that prevents it from replicating, killing rapidly dividing cells.
Name some Calcineurin inhibitors
Ciclosporin and Tacrolimus
How do Calcineurin Inhibitors work?
They form Drug/ Protein complexes which bind to and inhibit calcineurin, reducing Il-2 synthesis and t-helper cell action.
What are some ADRs of Calcineurin inhibitors
Hypertension and nephrotxicity.
What are some ADRs of cyclophosphamide?
Bladder cancer (due to excreted metabolite), leukaemia, lymphoma, infertility and teratogenesis.
What is mycophenolate mofetil?
An inhibitor of Inosine Monophosphate Dehydrogenase , an enzyme involved in T and B cell synthesis.
What are DMARDs and name the main drug, and 2 other classes
Disease modifying anti-rheumatic drugs. Methotrexate, and Aminosalicylates and Anti-TNF Agents.
How does methotrexate work?
Inhibits dihydrofolate reductase, decreasing purine/ DNA synthesis.
What are some ADRs of methotrexate apart from myelosupression?
Liver hepatitis/ cirrhosis, mucositis, teratogenesis.
What causes a methotrexate DDI?
Renal blood flow effectors, such as NSAIDs.
