BENICAR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for BENICAR (BENICAR).
Olmesartan medoxomil is a prodrug that is hydrolyzed to olmesartan, a selective angiotensin II receptor type 1 (AT1) antagonist. It blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II, reducing blood pressure.
| Metabolism | Prodrug olmesartan medoxomil is rapidly hydrolyzed to active olmesartan by esterases in gastrointestinal tract. Olmesartan is not metabolized by CYP450 enzymes and is excreted unchanged in bile and urine. |
| Excretion | Olmesartan is excreted primarily in feces (approximately 50–65%) via biliary elimination, with about 35–50% eliminated renally in urine as unchanged drug. |
| Half-life | Terminal elimination half-life is approximately 13–15 hours after multiple dosing, supporting once-daily dosing. |
| Protein binding | Highly protein-bound (approximately 99%) to serum albumin. |
| Volume of Distribution | Volume of distribution is approximately 17 L (0.2–0.3 L/kg), indicating limited extravascular distribution. |
| Bioavailability | Oral bioavailability is about 26–29% (absolute). |
| Onset of Action | Oral: Onset of antihypertensive effect occurs within 1–2 hours after a single dose. |
| Duration of Action | Duration of action is 24 hours, allowing once-daily dosing. Steady-state blood pressure reduction is achieved after 2 weeks. |
Initial: 20 mg orally once daily; titrate to 40 mg once daily. Maximum 40 mg/day.
| Dosage form | TABLET |
| Renal impairment | No adjustment for GFR ≥30 mL/min. For GFR <30 mL/min, initial dose 20 mg once daily; maximum 40 mg/day. |
| Liver impairment | No adjustment for mild to moderate hepatic impairment (Child-Pugh A or B). Not recommended in severe impairment (Child-Pugh C). |
| Pediatric use | Safety and efficacy not established for pediatric patients <18 years. |
| Geriatric use | Initial 20 mg once daily; caution due to potential for reduced renal function. Monitor BP and electrolytes. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for BENICAR (BENICAR).
| Breastfeeding | Minimal excretion into breast milk; M/P ratio is unknown. The American Academy of Pediatrics considers use compatible with breastfeeding, but caution is advised in preterm infants or those with renal impairment. |
| Teratogenic Risk | Pregnancy Category C (first trimester) and D (second and third trimesters). Exposure during the first trimester is associated with a potential risk of teratogenicity, though data are limited. Use in the second and third trimesters is known to cause fetal renal dysfunction, oligohydramnios, skull ossification deficits, and neonatal hypotension, hyperkalemia, and renal failure. |
■ FDA Black Box Warning
No FDA black box warning.
| Serious Effects |
["Concomitant use with aliskiren in patients with diabetes mellitus","History of hypersensitivity to any component of the product"]
| Precautions | ["May cause fetal harm if used during pregnancy","Avoid use in patients with severe renal impairment (CrCl <20 mL/min)","Sprue-like enteropathy (severe chronic diarrhea with weight loss)","Hypotension in volume-depleted patients","Hyperkalemia","Renal function deterioration in patients with renal artery stenosis"] |
| Food/Dietary | No significant food interactions; may be taken with or without food. However, avoid excessive intake of potassium-rich foods (e.g., bananas, oranges, spinach) if renal impairment is present or if taking potassium supplements. |
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| Fetal Monitoring | Monitor maternal blood pressure, renal function (serum creatinine, BUN), and urine protein. Perform fetal ultrasound to assess amniotic fluid volume, renal anatomy, and skull ossification if exposed during second/third trimester. Monitor neonatal blood pressure, potassium, and renal function after delivery. |
| Fertility Effects | No significant adverse effects on fertility reported in animal studies. In humans, no data suggest impairment of fertility or reproductive function. |
| Clinical Pearls | BENICAR (olmesartan) is an angiotensin II receptor blocker (ARB) used primarily for hypertension. It demonstrates a dose-dependent antihypertensive effect with a once-daily dosing regimen. Monitor renal function and serum potassium, especially in patients with renal impairment or those on potassium-sparing diuretics. Avoid use in pregnancy (category D). |
| Patient Advice | Take exactly as prescribed, usually once daily with or without food. · It may take 2-4 weeks to see full blood pressure lowering effect. · Do not take if pregnant or planning pregnancy; use effective contraception. · Avoid salt substitutes containing potassium unless approved by your doctor. · Report symptoms of high potassium (muscle weakness, slow heartbeat) or low blood pressure (dizziness, fainting). · Stay hydrated but avoid excessive dehydration (e.g., from diarrhea or vomiting). · Do not abruptly stop this medication without consulting your doctor. |