IV administered medications:

Question 1

Commonly prescribed IV medications in acute settings:

Answer 1

• Anti-emetics
• Antihistamine
• Proton pump inhibitors (PPI)
• Corticosteroid
• Frusemide
• Paracetamol

Question 2

Physiology of nausea and vomiting:

Answer 2

• vomiting is triggered by the emetic centre in the brain
• anti-emetics block neurotransmitters that trigger nausea and vomiting

Question 2

Metoclopramide:

Answer 2

• dopamine antagonist
• stimulates motility of upper GIT - increase rate of peristalsis and gastric emptying
• for treatment of most causes of N&V
• Adverse effects:
• GIT upset, restlessness, dizziness, fatigue, insomnia
• Interactions:
• enhances the absorption of some medications including diazepam and lithium
• potentiates effects of other CNS depressants
• Precautions:
• monitoring for medications associated with toxicity should be increased
• contraindicated in bowel obstruction and perforation due to increased peristalsis

Question 3

Promethazin:

Answer 3

• long-acting antihistamine with anti-cholinergic and anti-serotonin effect
• IV indications:
• nausea and vomiting
• sedation
• allergic reactions
• Adverse effects:
• hypotension, photosensitivity
• necrosis of subcutaneous tissue if extravasation occurs during IV injection
• Antihistamine effect:
• inhibits effects of histamine
• inhibits histamine receptors in inner ear
• adverse effects of antihistamine effect: sedation, incoordination, headache, insomnia, confusion anxiety, hallucinations, N&V

Question 3

Proton pump inhibitors:

Answer 3

• IV indication:
• short term treatment to relieve or prevent symptoms of hyperacidity until oral therapy is possible
• Action:
• suppress gastric acid secretion by blocking hydrogen ions required for production
• Examples:
• Omeprazole
• Esomeprazole

Question 3

5HT receptor antagonists:

Answer 3

• block specific serotonin receptors in the GIT and CNS to reduce the triggers for nausea and vomiting
• used to prevent and treat N&V
• administered via slow bolus injection or infusion
  *Indications:
• prophylaxis for chemotherapy and radiation associated nausea and vomiting
• post-operative N&V
• Examples:
• Ondansetron
• Tropisetron
• Adverse effects:
• headache, dizziness, fatigue, insomnia, constipation, diarrhoea, abdominal pain

Question 4

Ondansetron:

Answer 4

• given as a slow injection or infusion to prevent N&V caused by chemotherapy
• slow injection in the prevention or treatment in post-operative N&V
• adverse effects include flushing sensation, local reaction at IV site, dry mouth
• if given too rapidly can cause blurred vision

Question 5

Proton pump inhibitors 2:

Answer 5

• Precautions:
• interacts with a number of medications (check drug book)
• IV therapy only recommended for short term therapy
• increased risk of GI infections
• altered magnesium levels
• Adverse effects:
• GI symptoms, rash, headache, dizziness, IV site reaction/thrombophlebitis

Question 5

Diuretics: Frusemide:

Answer 5

• fast-acting diuretic
• works within 5 minutes when given IV
• IV use - pulmonary oedema, cerebral oedema or oedema associated with severe renal impairment
• Adverse effects:
• impaired glucose tolerance, hypokalaemia
• increased cholesterol and triglycerides
• increased incidence of gout
• check handbook for more interactions
• Administration:
• should NOT be given as a bolus
• should NOT be added to tubing of running IV
• maximum injection or infusion rate is 4mg/minute to avoid ototoxicity
• fluid balance and vital signs to be closely monitored because of risk of hypovolaemia

Question 6

IV corticosteroids:

Answer 6

• Therapeutic actions:
• immunosuppressive and anti-inflammatory
• suppresses inflammatory response including inhibiting inflammatory medicators
• IV indications:
• short term for inflammation associated with acute conditions
• autoimmune disorder
• allergies
• cerebral oedema
• monitoring:
• vital signs for signs of CVS impact or infection
• fluid and electrolyte monitoring: FBC, U&Es
• wound assessment
• BGL for hyperglycaemia

Question 7

IV paracetamol:

Answer 7

• Actions:
• analgesic and antipyretic actions are thought to be related to prostaglandin synthesis inhibition in the CNS
• IV indication is for mild to moderate pain
• Adverse effects:
• N&V, diarrhoea, dyspepsia, dizziness,
• increase in liver enzymes
• injection site pain and pruritus
• Precautions:
• caution if used in those with dehydration, hypovolaemia, chronic malnutrition, or chronic alcoholism
• caution if used in those with liver or kidney dysfunction. daily dose should not exceed 3g for liver disease