Problem: A client who is positive for HIV infection is prescribed zidovudine as part of the drug therapy. The client is age 66; has hypertension, diabetes, vitamin B12 deficiency; and has a drug history of insulin injections and vitamin B12 supplements. Why would the nurse administer zidovudine with caution to this client? zidovudine is contraindicated in clients with hypertension zidovudine may cause myelosuppression due to the client's age zidovudine may interact with the client's diabetes drug and cause adverse effects vitamin B12 deficiency increases the risk for severe hematologic toxicities