What is the recommended vitamin D (Vitamin D) supplementation dosage for a 31-year-old female with vitamin D deficiency (hypovitaminosis D) and a serum vitamin D level of 14 ng/mL?

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From the Guidelines

For a 31-year-old female with a vitamin D level of 14 ng/mL, I recommend starting with a high-dose vitamin D supplementation of 50,000 IU of vitamin D2 or D3 once weekly for 8 weeks, followed by maintenance therapy of 1,000-2,000 IU daily. This approach is based on the guidelines from the NCCN task force report on bone health in cancer care 1, which suggests that vitamin D should ideally be supplemented in amounts sufficient to bring serum 25(OH) D levels to 30 ng/ml (75 nmol/L) or higher. The two-phase approach is designed to rapidly correct the deficiency and then maintain adequate levels long-term.

Some key points to consider when implementing this treatment plan include:

  • The patient's serum 25(OH) D level should be rechecked after the 8-week loading dose regimen to ensure the deficiency has been corrected 1.
  • If the level remains below 30 ng/mL, another 8-week course of weekly high-dose therapy may be needed 1.
  • Vitamin D3 may be more effective in raising 25(OH) D concentrations and maintaining those levels for a longer time when longer dosing intervals are employed 1.
  • Calcium intake should also be optimized during treatment, aiming for 1,000-1,200 mg daily through diet or supplements to support bone health 1.

It's also important to note that vitamin D toxicity is uncommon but may occur with daily doses of more than 50,000 IU per day that produce 25(OH) D levels larger than 150 ng/mL 1. Therefore, monitoring the patient's vitamin D level and adjusting the treatment plan as needed is crucial to avoid toxicity.

From the FDA Drug Label

DIRECTIONS: Take 0ne (1) capsule each week, or as directed by your physician. Take with food. Each softgel capsule, for oral administration, contains Cholecalciferol, 1. 25 mg (equivalent to 50,000 USP units of Vitamin D).

The recommended dosage is one capsule (50,000 IU) per week, or as directed by a physician. For a 31-year-old female with a vitamin D level of 14, the dosage would be 50,000 IU per week. However, it is essential to consult a physician for personalized dosage instructions, as individual needs may vary 2.

  • Key considerations:
    • The patient's vitamin D level is low (14), which may require supplementation.
    • The recommended dosage is one capsule (50,000 IU) per week.
    • It is crucial to follow the physician's instructions for dosage and administration.

From the Research

Vitamin D Supplementation

To determine the appropriate amount of vitamin D to prescribe for a 31-year-old female with a vitamin D level of 14, we can look at the following guidelines:

  • A study published in 2011 3 suggests that a combination of calcium and vitamin D is effective in reducing the incidence of non-vertebral and hip fractures when administered at respective dosages of at least 1200 mg and 800 IU per day.
  • Another study from 1996 4 found that adding vitamin D to a calcium supplement resulted in significantly higher calcium excretion compared to calcium alone, with a dosage of 200 IU of vitamin D per day.
  • A 2020 study 5 used a dosage of 400 IU of vitamin D3 per day in combination with calcium and collagen peptides to examine the efficacy on bone turnover in postmenopausal women with osteopenia.

Key Findings

Some key points to consider when prescribing vitamin D supplementation:

  • The dosage of vitamin D used in various studies ranges from 200 IU to 800 IU per day.
  • Vitamin D supplementation is often used in combination with calcium to enhance absorption and efficacy.
  • The effectiveness of vitamin D supplementation can depend on various factors, including patient compliance and individual nutritional needs.

Considerations for Prescription

When prescribing vitamin D for a 31-year-old female with a vitamin D level of 14, consider the following:

  • The patient's vitamin D level is below the recommended range, indicating a need for supplementation.
  • A dosage of 800 IU per day may be considered, based on the study published in 2011 3.
  • It is essential to monitor the patient's vitamin D levels and adjust the dosage as needed to achieve optimal levels.
  • Combination with calcium supplementation may be beneficial to enhance absorption and efficacy, as suggested by studies 3, 4, and 5.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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