pharm question

[pv2007]

I need help with this question/situation. I think this would be appropriate, but not sure

Jane Morgan is admitted to the oncology unit for chemotherapy. Before administering a

chemotherapeutic agent that is known to cause allergic symptoms in patients,

diphenhydramine (Benadryl) is ordered. Discuss the rationale for this order.

If anaphylaxis develops in this client, would administering additional Benadryl help? If

not, what medication (including strength and dose) is recommended.

[caroladybelle, BSN, RN]

Doubt if this answers the question but here it goes.

The vast majority of chemo drugs that have high rates of hypersensitivity reactions, typical require from 2-5 premeds. On the minor end, Tylenol and Benedryl are given, usually accompanied by antinausea meds Decadron and a 5HT3 antiemetic. The decadron also helps prevent undue reactions. For some more dangerous drugs, IV Zantac/Tagamet or Solumedrol is added.

If Benedryl 50mg was used, and a hypersensitive reaction occurs, the MD usually escalates to some solumedrol/steroids, even though some may give some extra benedryl. If only 25mg are used, they will usually increase to 50mg benedryl.

But hypersensitive reactions to chemo vary, as does the associated treatment. There is anywhere from itching, hives to lifethreatening anaphylaxis where epinephrine and vasopressors are needed for stabilization.

[caroladybelle, BSN, RN]

In addition, some Biologic agents are not used with any steriods. In High dose IL2 dosing for Met. renal carcinoma or Met. melanoma, steroids are not used at all. And the patient frequently has to put up with a certain amount of itching/flushing with only atarax and sarna lotion.

The steroid in this case, would keep the chemo from doing its job for this particular treatment regimen. And would only be used if the patient had immediate lifethreatening complications.

[Daytonite, BSN, RN]

This is done all the time with administration of chemotherapy. It is also done with blood transfusions as well. I think if you do some more investigation you'll find coroboration for this. The rationale is that most of the chemotherapy protocols are just that, established protocols that are known to be effective against different types of cancers as proven by research. It is felt that the benefits of the drugs, the saving of a life, far outweigh their side effects. It is not just allergic reactions that are treated prophylactically, but other side effects as well (nausea, allopecia). My mother recently went through chemotherapy for breast cancer. Before her first dose she was given Decadron (in case of allergic reaction, I believe) and Zofran for nausea. Then before every subsequent injection she was given a huge dose of Zofran to counteract any nausea caused by the chemo.