Antiemetics Flashcards
what are antiemetics used for?
nausea/vomiting/motion sickness
Nursing consideration in antiemetic use?
- VS, i/o, dehydration, fluid and electrolyte imbalance
- limit oral intake to clear fluids when n/v
- SE = drowsiness; protect client from injury
Meclizine (Dramamine)
Functional Classification
Antiemetic, antihistamine, anticholinergic
Meclizine (Dramamine)
Mechanism of Action
Acts centrally by blocking chemoreceptor trigger zone, which in turn acts on vomiting center
Meclizine (Dramamine)
Uses
Vertigo, motion sickness
Meclizine (Dramamine)
Nursing Considerations
ASSESS:
- VERTIGO/MOTION SICKNESS: nausea, vomiting after 1hr; assess vertigo periodically
- Signs of toxicity of other products, masking of symptoms of disease: brain tumor, intestinal obstruction
- Observe for drowsiness, dizziness, level of consciousness
Metoclopramide (Reglan)
Functional Classification
Cholinergic, antiemetic
Metoclopramide (Reglan)
Mechanism of Action
Enhances response to acetylcholine of tissue in upper GI tract, which causes the contraction of gastric muscle; relaxes pyloric, duodenal segments; increases peristalsis without stimulating secretions; blocks dopamine in chemoreceptor trigger zone of CNS
Metoclopramide (Reglan)
Uses
Prevention of nausea, vomiting induced by chemotherapy, radiation, delayed gastric emptying, gastroesophageal reflux
Metoclopramide (Reglan)
Side Effects
SUICIDAL IDEATION, SEIZURES, EPS, NEUROLEPTIC MALIGNANT SYNDROME; TARDIVE DYSKINESIA (>3MO, HIGH DOSES)
Ondansetron (Zofran)
Functional Classification
Antiemetic
Ondansetron (Zofran)
Mechanism of Action
Prevents nausea, vomiting by blocking serotonin peripherally, centrally, and in the small intestine
Ondansetron (Zofran)
Uses
Prevention of nausea, vomiting associated with cancer chemotherapy, radiotherapy; prevention of postoperative nausea, vomiting
Ondansetron (Zofran)
Side Effects
CNS: Headache, Dizziness, Drowsiness, Fatigue, EPS
GI: Diarrhea, Constipation, abdominal pain, dry mouth
MISC: rash, BRONCHOSPASM (rare), Musculoskeletal Pain, Wound Problems, Shivering, Fever, Hypoxia, Urinary Retention
Ondansetron (Zofran)
Nursing Considerations
ASSESS:
- Absence of nausea, vomiting during chemotherapy
- Hypersensitivity reaction: rash, bronchospasm (rare)
- EPS: shuffling gait, tremors, grimacing, rigidity periodically
Prochlorperazine
Functional Classification
Antiemetic, antipsychotic
Prochlorperazine
Mechanism of Action
Decreases dopamine neurotransmission by increasing dopamine turnover through the blockade of the D2 somatodendritic autoreceptor in the mesolimbic system
Prochlorperazine
Uses
Nausea, Vomiting, Psychotic Disorders
Prochlorperazine
Contraindications
Hypersensitivity to phenothiazines, coma; infants, neonates, children <2yr; surgery
Prochlorperazine
Side Effects
CNS: NEUROLEPTIC MALIGNANT SYNDROME, CV: CIRCULATORY FAILURE, TACHYCARDIA, HEMA: AGRANULOCYTOSIS
Prochlorperazine
Nursing Considerations
ASSESS:
- EPS: abnormal movement, tardive dyskinesia, akathisia
- VS, BP; check patients with cardiac disease more often
- NEUROLEPTIC MALIGNANT SYNDROME: seizures, hypo/hypertension, fever, tachycardia, dyspnea, fatigue, muscle stiffness, loss of bladder control; notify prescriber immediately
- CBC, LFTs during course of treatment; blood dyscrasias, hepatotoxicity may occur
- Respiratory status before, during, after administration of emetic; check rate, rhythm, character; respiratory depression can occur rapidly among geriatric or debilitated patients
