click below
click below
Normal Size Small Size show me how
dental pharm
antineoplastic drugs & cancer therapy
Question | Answer |
---|---|
what is cancer? | the rapid, abnormal division of atypical cells into neoplasms, tumors that take over an area and are capable of relocating, metastasizing, and growing into a remote location |
apoptosis | programmed, natural cell death (good) |
angiogenesis | creation of new blood vessels=spread tumor cells (bad) |
chemotherapy | goal=to kill every viable tumor cell. directed at rapidly multiplying cells-not tumor specific so they kill ALL rapidly dividing cells-bone marrow, hair follicles, oral & intestinal mucosal cells (literally=controlled poisoning of pt) |
cell cycle: | S(DNA synthesis)-->G2 (premitotic)--> M(pro,meta,ana,telo)-->G1 (preparing for cell divison)-->G0 (resting phase) |
when is chemotherapy most effective? | in actively and rapidly dividing tumors-not so efficacious in slow growing (most cells in G0 phase)like lung,colon cancer |
alkylating agents | react with DNA,RNA,and proteins essential for cell divison.Cause cell death only when cell tries to divide.Leads to suppression of bone marrow,immune suppression,increased infections common |
Nitrogen Mustard | Alkylating agent-among 1st agents used |
Busulfan | Alkylating agent-anti-leukemia agent |
Nitrosureas | Alkylating agent-brain and GI neoplasms |
antimetabolites | resemble folic acid (essential vit. critical to formation of purines, & nucleic acids),purine and pyrimidine bases, and certain coenzymes |
Folic acid analogue | Methotrexate-widely used anticancer, rheumatoid arthritis, debilitating psoriasis. Can induce severe mucositis, bone marrow depression, extreme GI discomfort, bleeding. Points to newer uses in autoimmune diseases |
vinka alkaloids | Found to limit cell divison and cure lymphomas. Although natural cause, same side effects (from the vinca rosa shrub) |
antibiotics | products of strep bacteria-inhibit cell division by binding with DNA |
what are interferons and interleukins effective in? | certain cancers by augmenting the immune,antuproliferative response, and actions of nautral defense cells in the body |
what are interferon alpha and interleukin 2 used? | in melanomas, some leukemias, and Kaposi's sarcoma |
oral complications due to cancer therapy: | oral mucositis, salivary gland dysfunction, neurotoxicity, and infection |
oral mucositis | =most frequent complaint-inflammation and breakdown of oral mucosa:erythema w/ or w/o ulcerations |
causes of oral mucositis: | direct damage of chemo drug; emesis (throw-up) induces harmful acid to mucosa; normal physical trauma may be too much for compromised surface; abnormal and slow healing |
management of oral mucositis: | -bland rinses(Saline soln-q 15min to 4h)-topical anesthetics(viscous lidocaine sprays,benzocaine sprays/gels, diphenhydramine rinses)-mucosal coating agents (kaopectate soln; zilactin=lidocaine+film forming agent)-systemic agents(opiods, NOT NSAID) |
salivary gland dysfunction | irreversible w/ radiation, reversible w/ chemo |
management of salivary gland dysfunction | frequent rinses w/ saline, saliva substitutes, sugarless gum/candy, "supping" on H2O continuously, bethanecol, cevimeline, pilocarpine |
neuroroxicity | leads to severe, deep-seated throbbing pain that mimics dental pathology; dysguesia=taste change; TMJ disorders nay present due to sleep disruption, stress of tx |
management of neurotoxicity | must eliminate possiblilty of actual dental problem; palliative |
infection | immunosuppression & compromised mucosa leads to easier/more infections from normal flora and frequent candidal infections |
management of infections | Oral hygiene practices, antibacterial rinses, prechemotherapy preps |
radiation therapy complications | same complaints-more extensive and lasting problems; loss of salivary leads to change in flora (more S.mutans, lactobacillus) and higher caries incidence; topical fl; soft tissue and osteoradionecrosis |
what are the tx strategies for immunotherapy? | augmentation (vaccines) or suppression (useful in oragn transplants,grafts, or autoimmune diseases) |
immune stimulation-cell mediated immunity | in absence or deficiency of the thymus could implant immature fetal thymus to take over function in generalized cell mediated response; thymic extracts of calf thymus for specific disease states; levamisole (Ergamisol)-used for colorectal cancers, crohns |
levamisole | Ergamisol-used for colorectal cancers, crohn's disease |
immune stimulation-humoral immunity | (PASSIVE)due to congenital or aquired lack of certain immunoglobins.One means of tx=regular replacement therapy(passive immunity); antitoxins or antivenoms from active immunity in horses against snake bites or diphtheria |
immunosupression | (ACTIVE)most often used and most successful in organ or tissue transplants; cyclosporin (Restasis) |
cyclosporin | Restasis-used in organ transplants. bLocks interleukins and stops macrophages to prevent immune effect. Side effects=renal toxicity or hypertension. ALso useful vs. oral lichen planus (immunosupression) |
tacrolimus | Prograf-macrolide antibiotic that works like cyclosporin, except 100x stronger (immunosuppression) |
glucorticoids | Prednisone or Dexamethasone (immunosuppression) |
cytotoxic drugs | kills lymphocytes and interferes w/ cell proliferation (immunosuppression) |
cyclophosphamide | Cytoxan-developed for cancer therapy. Used now for autoimmune disease (immunosuppression) |
interferon beta 1b | Betaseron-used in tx of relapsing/remitting cases of multiple sclerosis.Most effective during pds of acute breakdown.Many side effects. Most commonly flu-like symptoms w/ start of therapy (immunosuppression) |