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Is amifostine (Ethyol, generic) still regularly used as a radioprotectant or has its use been discontinued in many centers? If so, was the discontinuation related to side effects? —Karen Seal, RN, OCN

Amifostine is used as a radioprotectant in patients undergoing treatment for squamous cell carcinoma of the head and neck. It is used to prevent acute or late xerostomia (dry mouth) when the radiation port includes a substantial portion of the parotid glands.1

In a study presented at the 2001 American Society of Clinical Oncology (ASCO) annual meeting, Boccia and colleagues concluded that low-dose amifostine (500 mg IV push over 3 minutes) is safe and well tolerated as a radioprotectant in patients with squamous cell carcinoma of the head and neck.2 Nausea, vomiting, and hypotension are the major side effects reported; however, prehydration and antiemetics can reduce the risk for these effects. Hypotension occurs in about 15% of patients.2

Prehydration can be administered at home orally or in clinic via IV. Any hypertensive medications should be held prior to amifostine administration. Nausea and vomiting occurs in 53% of patients; therefore, oral 5HT3 antagonists or a phenothiazine is given 90 to 120 minutes before administering amifostine. If an IV antiemetic is used, it can be given 30 minutes before. Dose, based on body surface area (BSA), is 200 mg/m2. BP should be checked prior to administering amifostine, and repeated at 5, 10, and 15 minutes postinjection. If hypotension occurs, 250-500 mL IV hydration should be infused until normotensive.

Amifostine use has declined with advances in radiation therapies, specifically intensity-modulated radiation therapy (IMRT), that are targeted to the cancer region. IMRT is a form of radiation that is able to avoid the parotid glands while still delivering radiation to target tissues.3 This reason, as well as adverse effects or poor tolerability, could be contributors to the decline in use of amifostine for this indication. —Sandra Cuellar, PharmD, BCOP


REFERENCES

1. Gosselin TK, Mautner B. Amifostine as a radioprotectant. Clin J Oncol Nurs. 2002;6(3):175-176.

2. Boccia RV, Alster M, Housekamp E. Amifostine (Ethyol) given by rapid IV push is safe and tolerable. Proc Am Soc Clin Oncol. 2001;20. Abstract 2543.

3. Mehta V. Amifostine (Ethyol) as a potential radioprotectant. http://cancergrace.org/radiation/2009/07/15/amifostine-intro/. Published July 15, 2009. Accessed September 17, 2012.


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