nisoldipine

Action

Suppresses calcium transport into vascular smooth muscle cells. This suppression inhibits vasoconstriction and dilates coronary arteries, improving myocardial oxygen uptake.

Availability

Tablets (extended-release): 8.5 mg, 17 mg, 22.5 mg, 34 mg

Indications and dosages

➣ Hypertension

Adults: Initially, 17 mg P.O. daily; may increase by 8.5 mg per week or longer intervals to attain adequate blood pressure control. Usual maintenance dosage is 17 to 34 mg daily.

Contraindications

• Hypersensitivity to drug or dihydropyridine calcium channel blockers

Precautions

Use cautiously in:

• heart failure and left ventricular dysfunction, hepatic impairment, renal disease, coronary artery disease, hypotension

• concurrent phenytoin use

• elderly patients

• pregnant or breastfeeding patients

• children (safety not established).

Administration

• Give with meals, but not with high-fat meals, grapefruit, or grapefruit juice.

• Don't crush or break extended-release tablets. Make sure patient swallows them whole.

• Know that drug may be given alone or with other antihypertensives.

Adverse reactions

CNS: headache, dizziness

CV: peripheral edema, chest pain, vasodilation, hypotension, palpitations

EENT: pharyngitis, sinusitis

GI: nausea

Skin: rash

Interactions

Drug-drug. Cimetidine: increased nisoldipine blood level

Phenytoin, other CYP3A4 inducers: decreased nisoldipine blood level and efficacy

Drug-food. Grapefruit juice: significantly increased drug blood level and effects

High-fat meal: decreased drug blood level

Drug-herbs. Ephedra (ma huang), yohimbine: antagonism of nimodipine effects

St. John's wort: decreased nimodipine blood level

Drug-behaviors. Alcohol use: increased hypotensive effects

Patient monitoring

• Check vital signs and ECG.

• Monitor fluid intake and output. Watch for peripheral edema.

Patient teaching

• Tell patient to swallow extended-release tablets whole and not to crush or break them.

• Advise patient to take with food, but not high-fat food. Recommend small, frequent meals.

• Instruct patient to avoid high-fat meals, alcohol, grapefruit, and grapefruit juice.

• Tell patient to immediately report irregular heart beat, shortness of breath, swelling, pronounced dizziness, rash, or chest pain.

• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs, foods, herbs, and behaviors mentioned above.