Histamine- 2 (H2) Antagonist

Question 1

Histamine- 2 (H2) Antagonist Drug Names

Answer 1

Cimetidine
Ranitidine
Famotidine

“-tidine”

Question 2

Histamine- 2 (H2) Antagonist Therapeutic Actions

Answer 2

• Selectively block histamine-2 receptor sites
• This blocking leads to a reduction in gastric acid secretion and reduction in overall pepsin production

• Block the release of hydrochloric acid in response to gastin

Question 3

Histamine- 2 (H2) Antagonist Indications

Answer 3

• Short-term treatment of active duodenal ulcer or benign gastric ulcer
• Treatment of pathological hypersecretory conditions such as Zollinger–Ellison syndrome
• Prophylaxis of stress-induced ulcers and acute upper GI bleeding in critical patients
• Treatment of erosive gastroesophageal reflux
• Relief of symptoms of heartburn, acid indigestion, and sour stomach (OTC preparations)

Question 4

Histamine- 2 (H2) Antagonist Contraindications and Cautions

Answer 4

Contraindications:
• Known allergy

Caution:
• Pregnancy
• Hepatic or renal function

Question 5

Histamine- 2 (H2) Antagonist DDI

Answer 5

DDI:
• Warfarin, phenytoin, beta blockers, alcohol, quinidine, lidocaine, theophylline, chloroquine, benzodiazepines, nifedipine, pentoxifylline, tricyclics, procainamide, and carbamazepine

Question 6

Histamine- 2 (H2) Antagonist Adverse Effects

Answer 6

• GI effects
• CNS effects
• Cardiac arrhythmias and hypotension

Question 7

Histamine- 2 (H2) Antagonist:

Assessment

Answer 7

Assess:
Hx: Allergy, lactation and pregnancy, renal function
Physical: vital signs, abdominal assessment, mucus membrane (baseline)
Labs: renal function, electrolytes

Question 8

Histamine- 2 (H2) Antagonist:

Diagnosis

Answer 8

Dx:

• Acute pain
• Disturbed sensory perception (kinesthetic, auditory)
• Risk for injury
• Decreased cardiac output
• Deficient knowledge

Question 9

Histamine- 2 (H2) Antagonist:

Implementation

Answer 9

Implementation:
• Administer oral drug with or before meals and at bedtime
• Decreased dose if hepatic or renal dysfunction
• Monitor the patient closely if giving IV
• Assess the patient carefully for any potential drug–drug interactions
• Provide comfort, including analgesics, ready access to bathroom facilities, and assistance with ambulation
• Safety measures
• Provide patient teaching

Question 10

Histamine- 2 (H2) Antagonist:

Evaluation

Answer 10

Eval:
Response to the drug 
Adverse effects
 Effectiveness of comfort measures
Compliance with regimen
Effectiveness of teaching plan