Vomiting with chemotherapy

Motion sickness is caused by stimulation of the vestibular system. This area contains many histaminic (Hj) and muscarinic cholinergic receptors. The higher brain (i.e., cerebral cortex) is affected by sensory input such as sights, smells, or emotions that can lead to vomiting. This area is involved in anticipatory nausea and vomiting associated with chemotherapy. 

Provide patient education regarding common toxicities associated with chemotherapy, such as nausea/vomiting, mucositis, myelosuppression, and alopecia. 

Metoclopramide is used for its antiemetic properties in patients with diabetic gastroparesis and with dexamethasone for prophylaxis of delayed nausea and vomiting associated with chemotherapy administration. 

Both omeprazole, a proton pump inhibitor and paclitaxel, a taxane cytotoxic may cause nausea and vomiting as side-effects. Prednisolone, as with other corticosteroids, does not cause nausea and vomiting. Corticosteroids such as dexamethasone are administered to relieve nausea and vomiting, particularly that associated with chemotherapy. 

Ondansetron is a 5HT3 antagonist indicated as an anti-emetic agent in nausea and vomiting associated with chemotherapy. The dose administered depends on the emetogenic degree of the chemotherapeutic agents used. 

Mechanism of Action A S-HT, receptor antagonist that acts centrally in the chemore-ceptor trigger zone and peripherally at the vagal nerve terminals. Therapeutic Effect Prevents nausea and vomiting associated with chemotherapy. 

It is indicated in neurotic, reactive, masked endogenous, recurrent depression depression with insomnia, depression, enuresis, panic disorder, neurogenic pain, urticaria and nausea and vomiting during chemotherapy maniac depressive psychosis in depressive phase. 

This may be given orally, intravenously (IV) or intramuscularly (IM) the dose depends on the indication. For postoperative nausea and vomiting, common regimens are either 8 mg orally before or 4 mg IV intra-operatively. Increasing the dose does not significantly improve its efficacy. The doses used with chemotherapy are larger, especially with cisplatin therapy, e.g. 8 mg IV before, then 8 mg 2-4 hours later then 8 mg 12-hourly for 5 days. 

Ondansetron is also available in an oral formulation, which can be used for mildly or moderately emetogenic chemotherapy. In one double-blind trial in 318 patients taking combinations of cyclophosphamide with methotrexate and/or doxorubicin, oral ondansetron 1, 4, or 8 mg t.i.d. for 3 d was completely effective in preventing emesis in 57,65, and 66% of patients, respectively, compared to 19% who did not vomit with placebo. 

The FDA, in 1985, gave approval for the use of two psychoactive chemicals from marijuana to prevent nausea and vomiting after chemotherapy in cancer treatment. THC can be prescribed in capsule form for these patients. Research suggests that compounds, other than THC, inhaled when smoking marijuana can also be used for medicinal purposes. Marijuana may help stop the weight loss in AIDS patients, it might lower eye pressnre in people with glaucoma, it may control spasms in multiple sclerosis patients, and it could be used to relieve chronic pain. 

Clinical use Prevention of nausea and vomiting, espedally that associated with chemotherapy, surgical procedures, and radiotherapy. Prevention of nausea and vomiting, especially that associated with chemotherapy, surgical procedures, and radiotherapy. 

Marijuana has been used effectively to treat the nausea and vomiting often associated with chemotherapy in the treatment of cancer. 

Cannabis and THC synthetics have Iwen used to counter the nausea and vomiting frequently associated with chemotherapies (and some radiation treatments) for cancer. These side effects, which can last for several hours or even several days, often are not ameliorated by traditional antiemetic medications (although significant advances arc being made in the development of more powerful antisickness drugs). Researchers in... 

Tropisetron [ICS-205,930, Novoban, (172) in Fig. 14.18 Novartis] is a potent 5-HT, receptor antagonist = 0.38-3.1 nM) (483-485)that has recently been found to possess a, nAChR subtype antagonist activity (437) (see Table 14.13) and a, nAChR partial agonist activity (445). In rat behavioral studies, tropisetron attenuated scopolamine-induced memory deficits in the passive-avoidance test (438), and spatial navigation deficits in the Morris water-maze task (463), and improved the retention of a conditioned response in rats with p-chloroamphetamine-induced deficits (486). Tropisetron is currently marketed for the treatment of nausea and vomiting associated with chemotherapy treatments (485). 

Although marijuana is the most frequently used illicit drug, it does have some limited legitimate medicinal use. Dronabinol (Marmol) contains synthetic THC and is used to treat anorexia and nausea in AIDS patients, nausea and vomiting associated with chemotherapy, and asthma and glaucoma, ... 

The primary goal with chemotherapy-induced nausea and vomiting (CINV) is to prevent nausea and/or vomiting. 

The role of interferon in advanced disease is even more unclear, especially for those patients who have recurred after treatment with adjuvant interferon therapy. Interferon-a has been used as a single agent in patients with metastatic disease who have not received adjuvant therapy, and in combination with chemotherapy and/or other biotherapy for metastatic melanoma. The challenges of combination therapy are that many of the toxicities seen with interferon can be exacerbated by concomitant chemotherapy (e.g., nausea, vomiting, and neutropenia). In an attempt to limit systemic toxicity and to potentate local benefits, the regional administration has been evaluated in a variety of settings. Intralesional and perilesional application of interferon has been shown to have some efficacy in small lesions and appears to be well tolerated. ... 

As previously noted, it is essential that the oncology pharmacist be well versed in the pharmacotherapy-based management of severe pain, infection, and the nausea, vomiting, and fatigue associated with chemotherapy. The provision of contemporary and valid drug information to patients and families is essential, as is assistance in helping with the interpretation of information that patients and loved ones secure either through their health care providers or independently (e.g., from the Internet). 

The use of the maitake D fraction can ameliorate varions side effects secondary to chemotherapy. Beneficial improvements were found in 90% of patients and included ameliorations of lost appetite, vomiting, nausea, and hair loss as well as increased counts of white blood cell pain was reduced in 83%. It is worth repeating that there are strong indications that while maitake extract contributes to tumor reduction without a high loss of white blood cells, it also reduces in many cases pain, hair loss, nausea, and other side effects usually associated with chemotherapy. 

Acceptable, but limited, medical uses have been found for THC. The pharmaceutical company Unimed manufactures Marinol , currently the only manufactured drug containing a synthetic isomer of THC (dronabinol) in its formulation. Marinol is listed on Schedule III. The medicine is used to stimulate the appetite in AIDS patients and to treat nausea and vomiting associated with chemotherapy. The synthesis of THC and cannabinols is difficult and complex thus, there is little reason to expect clandestine synthesis to be a factor in the restricted legal use of marijuana. 

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