Antiemetics, administration

Cisplatin administration requires adequate hydration and forced diuresis to prevent kidney damage. Cisplatin is intensely emetogenic and its use requires adequate antiemetic prophylaxis. Myelosuppression is less evident than with other alkylating agents. 

Patients receiving cytotoxic chemotherapy very often need concomitant administrating of antiemetic therapy. Such protocols will start well in advance of administering the cytotoxic, and last for a reasonable time with regard to pharmacokinetics of the antineoplastic agent. In addition, side effects of antineoplastic therapy are made better tolerable by supportive care. 

Antineoplastic drugs are potentially toxic and their administration is often associated with many serious adverse reactions. At times, some of these adverse effects are allowed because the only alternative is to stop treatment of the malignancy. A treatment plan is developed that will prevent, lessen, or treat most or all of the symptoms of a specific adverse reaction. An example of prevention is giving an antiemetic before administering an antineoplastic drug known to cause severe nausea and vomiting. An example of treatment of the symptoms of an adverse reaction is the administration of an antiemetic and intravenous (IV) fluids and electrolytes when severe vomiting occurs. 

A few antineoplastic drugs require treatment measures before administration. An example of preadiniiiistration treatment is hydration of the patient witii 1 to 2 liters of IV fluid infused before administration of cisplatin (Platinol) or administration of an antiemetic before the adiniiiistration of mechbretiiamine These measures are ordered by the primary health care provider and, in some instances, may vary slightly from the manufacturer s recommendations. 

Simple Self-limiting, resolves spontaneously and requires only symptomatic therapy Complex Not relieved after administration of antiemetics progressive deterioration of patient secondary to fluid-eledrolyte imbalances usually associated with noxious agents or psychogenic events... 

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. 

Nausea and vomiting that occur within 24 hours of chemotherapy administration is defined as acute, whereas when it starts more than 24 hours after chemotherapy administration, it is defined as delayed. The emetogenic potential of the chemotherapeutic agent or regimen (see Table 27-2) is the primary factor to consider when selecting an antiemetic for prophylaxis of CINV. 

Patients receiving chemotherapy that is classified as being of high emetic risk should receive a combination antiemetic regimen containing three drugs on the day of chemotherapy administration (day 1)—an SSRI plus dexamethasone plus aprepitant. 

A combined administration of metoclopramide and anticholinergic agent to reduce dystonic reactions of metoclopramide, did not diminish antiemetic efficacy in dogs [117], Thus, the inhibitory effect on GI smooth muscle by cholinergic blockade had no significant impact on antiemetic activity of metoclopramide. 

Gavini E, Rassu G, Sanna V, Cossu M, Giunchedi P (2005) Mucoadhesive microspheres for nasal administration of an antiemetic drug, metoclopramide in-vitro/ex-vivo studies. J Pharm Pharmacol 57 287-294. 

Antiemetic Initially, give 5 mg/m 1 to 3 hours prior to the administration of chemotherapy, then every 2 to 4 hours after chemotherapy is given, for a total of 4 to 6 doses/day. If the 5 mg/m dose is ineffective, and there are no significant side... 

Meperidine (Demerol) [C-ll] [Narcotic Analgesic] Uses Moderate/ severe pain Action Narcotic analgesic Dose Adults. 25-50 mg IV, 50-100 mg IM Peds. 1 mg/kg IV/IM (onset w/in 5 min IV and 10 min IM duration about 2 h) Caution [C, ] Contra Convulsive disorders and acute abdomen Disp Prefilled 1 mL syringes 25, 50, 75, 100 mg/mL various amps and vials oral syrup and tabs SE N/V (may be severe), dizziness, weakness, sedation, miosis, resp d ession, xerostomia (dry mouth) Interactions t CNS depression W/ opiates, sedatives/ hypnotics TCNS stimulation W/amphetamines t risk of tox W7 phenytoin EMS Pt should be receiving O2 prior to administration have resuscitation equipment and naloxone available naloxone can be used as an antidote to reverse resp depression aspirate prior to IM administration inadv tent IV admin of IM doses may cause tach and syncope mix w/ NS to make a 10 mg/mL soln and inj very slowly N/V may be sev e may premedicate w/ an antiemetic... 

Mechanism of Action A phenothiazine derivative that blocks dopamine at postsynap-tic receptor sites. Possesses strong extrapyramidal and antiemetic effects and weak anticholinergic and sedative effects. Therapeutic Effect Suppresses behavioral response in psychosis reduces locomotor activity and aggressiveness. Pharmacokinetics Readily absorbed following PO administration. Protein binding 90%-99%. Metabolized in liver. Excreted in urine. Half-life 24 hr. 

The risk of tachycardia, hypertension, and cardiotoxicity is increased with coadministration of dronabinol (an antiemetic) and dextroamphetamine. In addition, administration of dextroamphetamine with MAOIs may increase the risk of hypertensive crisis. Al-kalinizing agents can speed absorption (e.g., antacids) or delay urinary excretion (e.g., acetazolamide, thiazide diuretics) of dextroamphetamine, thus potentiating its effects. Gastric or urinary acidifying agents (e.g., ascorbic acid, ammonium chloride) can decrease the effects of dextroamphetamine. Propoxyphene overdose can potentiate amphetamine central nervous system stimulation, potentially resulting in fatal convulsions. 

Pregnancy can be prevented following coitus by the administration of estrogens alone, progestin alone, or in combination ("morning after contraception). When treatment is begun within 72 hours, it is effective 99% of the time. Some effective schedules are shown in Table 40-4. The hormones are often administered with antiemetics, since 40% of the patients have nausea or vomiting. Other adverse effects include headache, dizziness, breast tenderness, and abdominal and leg cramps. 

In 15 men with osteonecrosis of the femoral head after short-term therapy the mean duration of therapy was 21 (range 7-39) days and the mean dose in milligram equivalents of prednisone was 850 (range 290-3300) mg (269). The time from administration of glucocorticoids to hip pain was 17 (range 6-33) months. A new case of bilateral avascular necrosis of the femoral heads after high-dose short-term dexamethasone therapy as an antiemetic in cancer chemotherapy has been reported (270). 

Tropisetron is a synthetic TTA containing an esterified tropine moiety (Fig. 1). This drug is a potent antiemetic selective 5-HT3 receptor antagonist to treat postoperative and chemotherapy-induced vomiting and nausea by daily intravenous or oral administration [70], Furthermore, tropisetron is a potent and selective partial agonist of a7-nAChR [39],... 

Aspirin, paracetamol, and hydrocortisone are used to control febrile reactions of amphotericin. Patients with a history of adverse effects with amphotericin should be prophylactically treated with antipyretics and hydrocortisone. Antiemetics and pethidine also are used for the treatment of adverse effects of amphotericin. With sodium supplements and hydration therapy, damage to the kidney can be reduced. If conventional amphotericin is not well tolerated by the patient, colloidal carriers can be used as alternative options. Administration of amphotericin with a nephrotoxic drug, such as cyclosporin, may further increase toxicity. Diuretics and anticancer drugs should be avoided with amphotericin. 

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