Is Procardia XL 60 mg Q Daily Equivalent to 30 mg XL Given Twice Daily?
Condition: Hypertension in Pregnancy; Hypertension in Postpartum
MeSH terms: Hypertension, Pregnancy-Induced; Hypertension
Intervention: Procardia XL 30Mg; Procardia XL 60Mg
Intervention description: Procardia XL 30 mg XL Q 12h; Procardia XL 60 mg Q 24h
Intervention MeSH terms: Nifedipine
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Depending on the group the person gets randomized into they will receive 60 mg of nifedipine at 0h vs 30 mg of nifedipine at 0h followed by 30 mg extra at 12h, These medications will be administered by a nurse or physician on the floor.
After 12h and at the end of the 24h (plus or minus 30 min) a blood sample (2cc) with be obtained and sent to Mount Sinai Hospital to determine serum Procardia levels. This blood samples will be stored until this research study is finished and will be disposed after. A total of 20cc of blood will be obtained from each patient.
Also the patient will take a survey of side effects of the BP medication. BPs will be measured Q 4h and documented at 0h, 4h, 8h, 12h, 16h, 20h and 24h (plus or minus 30 min)
Masking: None (Open Label)
Enrollment: 5.0
Sex: Female
Minimum age: 18 Years
Maximum age: 55 Years
Healthy volunteers: No
Keywords: chronic hypertension; postpartum hypertension; preeclampsia; treatment; Procardia XL

Summary:

      Antihypertensive therapy has been used in pregnant patients antepartum to improve blood
      pressure (BP) elevation in cases of chronic hypertension, and postpartum for persistent
      hypertension after delivery in cases of gestational hypertension and preeclampsia, as well as
      for management of chronic hypertension.

      There is limited evidence regarding the precise BP level at which antihypertensive therapy is
      indicated during pregnancy for chronic hypertension. Treatment has been suggested in pregnant
      patients when systolic BP is ≥ 160 mmHg and at a lower diastolic BP threshold of 105 mm Hg,
      however some providers may initiate therapy at systolic BPs ≥ 150 mmHg.

      Nifedipine is a peripheral arterial vasodilator and an ideal first line antihypertensive
      agent due to its low maternal side-effect profile. It has been proven to be safe in
      pregnancy. Conventional nifedipine can be started at 10 mg twice daily with a maximum dose of
      120 mg/d, but frequently extended release tablets are preferred due to steady blood pressure
      control with once daily administration.

      It is frequently used however as a twice daily dosing as many providers have noticed an
      increase in the BPs 12-24h from administration. Twice daily dosing might produce overlapping
      profiles that prevent elevation of BP at the time of the next administration and breakthrough
      elevations throughout the day in pregnant women.

      The aim of this study is to investigate the mean plasma levels and standard deviations of
      Procardia at 24h after Procardia XL is administered as a 60 mg daily dose and the mean plasma
      levels after it is given as a 30 mg twice-daily dose. This will be a pilot study for a future
      randomized control trial that will allow the researchers to determine whether 60 mg daily of
      Procardia XL is equivalent to 30 mg twice daily. Secondary outcome will be effective control
      of BP throughout the day (0h, 4h, 8h, 12h, 16h, 20h and 24h) defined as BPs below 160/105 as
      well as side effects of nifedipine as reported by patients.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Antepartum or postpartum patients between the age of 18-55 requiring 60 mg of
             Procardia XL to control elevated blood pressures secondary to preeclampsia,
             gestational hypertension, or chronic hypertension.

        Exclusion Criteria:

          -  All patients receiving other antihypertensive medication

          -  All patients with a contraindication to nifedipine: Hypersensitivity to nifedipine or
             other calcium -channel blocker, cardiogenic shock, concomitant administration with
             strong CYP34A inducers (rifampin, rifabutin, phenobarbital, phenytoin, carbamazepine,
             St Johns Wort) → significantly reduces nifedipine efficacy, impaired liver function→?
             Patients with hepatic impairment (liver cirrhosis) have a longer disposition half-life
             and higher bioavailability of nifedipine than healthy volunteers

          -  Patients over the age of 55