Phosphorus Oral Supplements

[01 August 2014]

Products Affected - Description

Phos-NaK Powder, Cypress Pharmaceuticals
1.5 gram packet, 100 count package (NDC 60258-0006-01)

Reason for the Shortage

Cypress Pharmaceuticals has Phos-Nak Powder on back order due to manufacturing delays.1

Available Products

K-Phos Neutral Tablet, Beach Pharmaceuticals
100 count package (NDC 00486-1125-01)
500 count package (NDC 00486-1125-05)

K-Phos Original Tablet, Beach Pharmaceuticals
100 count package (NDC 00486-1111-01)
500 count package (NDC 00486-1111-05)

K-Phos No. 2 Tablet, Beach Pharmaceuticals
100 count package (NDC 00486-1134-01)

Phospha 250 Neutral Tablet, Rising Pharmaceuticals
100 count package (NDC 64980-0104-01)

Estimated Resupply Dates

Cypress has Phos-Nak Powder on intermittent back order and is releasing product as it becomes available. Product may be available at pharmacy wholesalers.1

Implications for Patient Care

Oral phosphate supplements are used to increase serum phosphorus levels and acidify the urine to solubilize urinary calcium. Excessive renal loss or inadequate gastrointestinal absorption can lead to decreased phosphorus levels. Phosphates also reduce odor and rash caused by ammonia in the urine.4-10

Alternative Agents & Management

  • Clinicians will have to base their alternative choice on patient specific criteria. The table below provides a comparison of oral products.
  • Monitor renal function, serum sodium, serum phosphorus, serum potassium, and serum calcium levels during therapy.5
Table. Comparison of Oral Phosphorus Products 4-10

Phosphorus Oral Products

How Supplied

NDC Number








Phos-NaK powder

1.5 gm packets, 100 count



250 mg

(8 mmol)

280 mg

(7.1 mEq)

160 mg

(6.9 mEq)

K-Phos Neutral

Tablets,100 and 500 count




250 mg

(8 mmol)

45 mg

(1.1 mEq)

298 mg

(13 mEq)

K-Phos Original Dissolvable Tablets

Tablets, 100 and 500 count




114 mg

(3.7 mmol)

144 mg

(3.7 mEq)


K-Phos No. 2

Tablets, 100 count



250 mg

(8 mmol)

88 mg

(2.3 mEq)

134 mg

(5.8 mEq)

Phospha 250 Neutral

Tablets, 100 count



250 mg

(8 mmol)

45 mg

(1.1 mEq)

298 mg

(13 mEq)

Related Shortages


  1. Cypress Pharmaceuticals (personal communications). April 30, June 25, and July 7 and 30, 2014.
  2. Beach Pharmaceuticals (personal communications). April 29, and July 30, 2014.
  3. Rising Pharmaceuticals (personal communications). April 29, 2014.
  4. Lacy CF, Armstrong LL, Godman MP, Lance LL, eds. Lexi-Drugs Online. Hudson, OH: Lexi-Comp; 2014.
  5. Wickersham RM, Novak KK, Horenkamp JR, et al., eds. Drug Facts and Comparisons (updated monthly). St. Louis, MO: Wolters Kluwer Health / Facts and Comparisons; 2014.
  6. Phos-NaK [product information]. Madison, MS: Cypress Pharmaceuticals, Inc; October 2002.
  7. Phospha 250 Neutral [product information]. Allendale, NJ: Rising Pharmaceuticals, Inc; October 2013.
  8. K-Phos Original [product information]. Tampa, FL: Beach Pharmaceuticals; July 2009.
  9. K-Phos Neutral [product information]. Tampa, FL: Beach Pharmaceuticals; July 2009.
  10. K-Phos No. 2 [product information]. Tampa, FL: Beach Pharmaceuticals; July 2009.


Created August 1, 2014 by Kristen Jefferies, PharmD, Drug Information Specialist and David M. Peterson, PharmD, Drug Information Specialist. Copyright 2014, Drug Information Service, University of Utah, Salt Lake City, UT.


This information is provided through the support of Novation to ASHP solely as a service to its members, which shall not use this information for their further commercial use. The content was prepared by the Drug Information Center of University of Utah. Novation, ASHP, and the University of Utah make no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, which respect to such information, and specifically disclaim all such warranties. Users of this information are advised that decisions regarding the use of drugs and drug therapies are complex medical decisions and that in using this information, each user must exercise his or her own independent professional judgment. Neither Novation, ASHP nor the University of Utah assumes any liability for persons administering or receiving drugs or other medical care in reliance upon this information, or otherwise in connection with this bulletin. Neither Novation, ASHP nor University of Utah endorses or recommends the use of any drug.

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