II. Mechanism

  1. Nifedipine (Procardia) is prototype for class
  2. Dihydropyridine Calcium Channel Blockers
    1. Dihydropyridines are primarily active at vascular Smooth Muscle
    2. Contrast with Non-Dihydropyridines which are also active at cardiac Smooth Muscle

III. Contraindications

  1. Consider avoiding in Diabetes Mellitus (relative contraindication)
    1. May increase Proteinuria
  2. NOT contraindicated in combination with Beta Blockers
    1. Contrast with Non-Dihydropyridine Calcium Channel Blockers (Diltiazem, Verapamil) which slow AV nodal conduction

IV. Drug Interactions

  1. Clarithromycin
    1. Increases Calcium Channel Blocker levels via CYP3A4 inhibition especially with Dihydropyridines and over age 65 years
      1. Provokes Hypotension and Bradycardia
      2. Risk of Acute Kidney Injury (often requiring hospitalization)
    2. References
      1. Gandhi (2013) JAMA 310(23):2544-53 [PubMed]

V. Preparations: Oral

  1. Amlodipine (Norvasc)
    1. Dosing
      1. Typical dose: 5 mg orally daily (may start at 2.5 mg daily in elderly)
      2. Maximum: 10 mg orally daily (little benefit over 5 mg, but increased edema)
    2. Advantages
      1. Preferred first line oral antihypertensive Calcium Channel Blocker
      2. Long acting and less reflex Tachycardia than other Dihydropyridines, with improved cardiovascular outcomes
      3. Does not exacerbate Left Ventricular Dysfunction
  2. Nifedipine (Procardia)
    1. Consider in Hypertension control in pregnancy (long safety record)
  3. Felodipine
  4. Nimodipine (Nymalize)

VI. Preparations: Parenteral (Hypertensive Emergency)

  1. Background
    1. Counter Cerebral Vessel spasm (e.g. early Subarachnoid Hemorrhage, CVA)
  2. Clevidipine (Cleviprex)
  3. Nicardipine

VII. Adverse Effects

  1. See Calcium Channel Blocker
  2. Peripheral Edema (Norvasc)
    1. Occurs more commonly in women
    2. Occurs more commonly on Norvasc doses >5 mg
    3. Adding ACE Inhibitor to regimen decreases edema
    4. Avoid Diuretics to reduce Dihydropyridine -induced edema
      1. Dihydropyridine-induced edema mechanism is vasodilation fluid leak into interstitium, NOT Sodium and water retention

VIII. References

  1. (2022) Presc Lett 29(11): 64-5

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Related Studies

Cost: Medications

amlodipine (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
AMLODIPINE BESYLATE 10 MG TAB Generic $0.02 each
AMLODIPINE BESYLATE 2.5 MG TAB Generic $0.01 each
AMLODIPINE BESYLATE 5 MG TAB Generic $0.01 each
AMLODIPINE-ATORVAST 10-10 MG Generic $1.09 each
AMLODIPINE-ATORVAST 10-20 MG Generic $2.38 each
AMLODIPINE-ATORVAST 10-40 MG Generic $1.32 each
AMLODIPINE-ATORVAST 10-80 MG Generic $4.03 each
AMLODIPINE-ATORVAST 5-10 MG Generic $2.08 each
AMLODIPINE-ATORVAST 5-20 MG Generic $1.13 each
AMLODIPINE-ATORVAST 5-40 MG Generic $1.50 each
AMLODIPINE-BENAZEPRIL 10-20 MG Generic $0.15 each
AMLODIPINE-BENAZEPRIL 10-40 MG Generic $0.16 each
AMLODIPINE-BENAZEPRIL 2.5-10 Generic $0.11 each
AMLODIPINE-BENAZEPRIL 5-10 MG Generic $0.11 each
AMLODIPINE-BENAZEPRIL 5-20 MG Generic $0.13 each
AMLODIPINE-BENAZEPRIL 5-40 MG Generic $0.16 each
AMLODIPINE-OLMESARTAN 10-20 MG Generic $0.39 each
AMLODIPINE-OLMESARTAN 10-40 MG Generic $0.40 each
AMLODIPINE-OLMESARTAN 5-20 MG Generic $0.36 each
AMLODIPINE-OLMESARTAN 5-40 MG Generic $0.45 each
AMLODIPINE-VALSARTAN 10-160 MG Generic $0.54 each
AMLODIPINE-VALSARTAN 10-320 MG Generic $0.70 each
AMLODIPINE-VALSARTAN 5-160 MG Generic $0.49 each
AMLODIPINE-VALSARTAN 5-320 MG Generic $0.58 each
norvasc (on 3/15/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
NORVASC 10 MG TABLET Generic $0.02 each
NORVASC 5 MG TABLET Generic $0.01 each