Pharmacologic: direct renin inhibitor
Treatment of hypertension (alone or with other agents).
Inhibition of renin results in decreased formation of angiotensin II, a powerful vasoconstrictor. Therapeutic Effects: Decreased blood pressure.
Adverse Reactions/Side Effects
Resp: cough. GI: abdominal pain, diarrhea ↑ (in females and elderly), dyspepsia, reflux. Misc: ANGIOEDEMA.
PHYSICAL THERAPY IMPLICATIONS
Examination and Evaluation
Monitor signs of angioedema including rashes, raised patches of red or white skin (welts), burning/itching skin, swelling in the face, and difficulty breathing. Notify physician of these signs immediately.
Assess blood pressure periodically, and compare to normal values (see Appendix F) to help document antihypertensive effects.
Remind patients to take medication as directed to control hypertension even if they are asymptomatic.
Counsel patients about additional interventions to help control blood pressure, including regular exercise, weight loss, sodium restriction, stress reduction, moderation of alcohol consumption, and smoking cessation.
Instruct patient to notify physician of a prolonged dry cough; drug therapy may need to be altered to resolve this side effect.
Instruct patient or family/caregivers to report severe or prolonged GI problems such as diarrhea, indigestion, heartburn, and abdominal pain.
Absorption: Poorly absorbed (bioavailability 2.5%).
Metabolism and Excretion: 2% excreted unchanged in urine, remainder is probably metabolized (CYP3A4 enzyme system).
Contraindicated in: Hypersensitivity; OB: May cause fetal injury or death; Concurrent use with cyclosporine.
Use Cautiously in: Salt or volume depletion (correct before use); Severe renal impairment; Pedi: Safety not established.
Drug-Drug: Blood levels are ↓ by irbesartan. Blood levels are ↑ by atorvastatin, ketoconazole, and cyclosporine (concurrent use with cyclosporine not recommended). ↓ blood levels and may ↓ effects of furosemide. Antihypertensive effects may be ↑ by other antihypertensives, diuretics, and nitrates. ↑ risk of hyperkalemia with concurrent use of ACE inhibitors, angiotensin II receptor antagonists, potassium supplements, potassium-sparing diuretics, or potassium-containing salt substitutes.
Drug-Food: High-fat meals significantly ↓ absorption.
PO (Adults): 150 mg/day initially; may be increased to 300 mg/day.