Oct 02, 2017
Carrie asked
Hello, I'm a medical student trying to write up a paper on upper GI endoscopy for patients with complex metabolic syndromes. Many of the patients are on sodium phenylbutyrate (I've been told pH 4) and sodium benzoate (pH 2), but I am struggling to find a reference for these two pH's. Please can you help me to find a reference for these two medications' acidity levels? Much obliged.
Answer
Both drugs by themselves don't have published pH values because they aren't commercially available as solutions. As I'm sure you know, pH refers to the acidity (or basicity) of an aqueous
solution. So what we are really looking for is the pH of a resulting solution. This obviously varies with what kind of solution we are talking about so we need some more information to find what you are looking for.
I did some research and came across the following study:
Am J Health Syst Pharm. 2007 Jul 15;64(14):1513-5.
Stability of extemporaneously prepared sodium phenylbutyrate oral suspensions.Caruthers RL1, Johnson CE.
In the study, they created the following solution:
An oral suspension of sodium phenylbutyrate 200 mg/mL was prepared by thoroughly grinding 12 g of Sodium Phenylbutyrate Powder, USP,a in a glass mortar. Thirty milliliters of Ora-Plus b and 30 mL of either Ora- Sweet c or Ora-Sweet SF d were mixed and added to the powder to make a final volume of 60 mL.
The study tested the stability of the preparation over 90 days... below are the results:
At least 95% of the initial concentration of sodium phenylbutyrate remained throughout the 90-day study period in all suspensions (Table 1). There was no detectable change in color, odor, and taste, and no visible microbial growth was observed in any sample. Both preparations were bitter with a strong, bitter aftertaste. Administering a masking agent, such as chocolate syrup or peanut butter, before and after medication administration is recommended to mask the bitter taste and improve palatability, especially for children. No appreciable change from the initial mean ± S.D. pH (7.52 ± 0.10) occurred in any of the samples made with Ora-Sweet or in those prepared with Ora-Sweet SF (7.50 ± 0.17).
