Editorial: Quality Assurance in Compounding, Part IX

United States Pharmacopeia (USP) Chapter <911> Viscosity

Viscosity can be used in a quality-assurance program for both incoming materials and final compounded preparations. Viscosity is the property of liquids that is closely related to their resistance to flow. The commonly used unit is the centipoise (cp). Example viscosities at 20�C of some liquids used in pharmacy include ethyl alcohol (1.19 cp), olive oil (100 cp), glycerin (400 cp), and castor oil (1,000 cp). Viscosity can also be determined for gels.

Equipment used to determine viscosity includes calibrated viscometer tubes (Cannon-Fenske and others), cup-type viscometers, and rotational viscometers. Those that are reasonably priced for pharmacy use would be the calibrated viscometer tubes and the cup-type viscometers that can all be used for liquids. For gels, the rotational viscometers would be required.

When compounding liquids using a Master Formula, the viscosity is a simple test that can be listed on the Master Formula record, performed during compounding and then documented on the Compounding Record. The viscosity should be relatively consistent between batches of the same formulation; if not, there may be a problem. Use of the viscometers generally involve temperature control and measuring the time it takes for the liquid to flow through a defined orifice. Commercial standards are available for calibration of the devices. Because these devices do not wear out they can be used for a long time.

Viscosity is another relatively inexpensive, simple-to-use testing method for documenting a physical characteristic of a liquid or gel.


Loyd V. Allen, Jr., PhD, RPh
Editor-in-Chief

Tuesday evening I had a new political experience. One of our Congressional Representatives, Mary Fallon, held a Town Hall meeting via telephone from Washington, DC. My wife and I both participated from home along with 645 others in the greater Oklahoma City area. The session lasted about an hour and a half and started with an update on the current issues and bills in Congress. It was then open for questions. If you wanted to ask a question, you simply pressed the "#" sign and you were placed in the queue. All phones were blocked from speaking except the one from where the question was coming; this eliminated background noise, etc. This is a simple, easy, and informative way to keep up to date on what's going on and to make a "general" contact with your elected congressional representatives and senators.


Loyd V. Allen, Jr., PhD, RPh
Editor-in-Chief

Interesting that we hear...

   ...the income tax system is broken

   ...the immigration system is broken

   ...the public educational system is broken

   ...the drug approval system is broken

What, then, is "working" in DC?

I guess it's the "re-election" campaigns; they seem to be going full speed ahead!!! It seems OUR politicians are more interested in staying in DC to be re-elected to work on their re-election campaigns again and again and again and again�. It would be nice if they wrote and voted on bills for the good of the country instead of for their re-election! Join hundreds of other pharmacists at Compounders on Capitol Hill and talk with your congressional members about WHY you voted for them!


Loyd V. Allen, Jr., PhD, RPh
Editor-in-Chief

Because of complaints about potential subpotency Spectrum and the U.S. Food and Drug Administration informed healthcare professionals of a nationwide recall of 3 lots (TS0225, UK0821, and V11203) of Caffeine Citrated, Powder, Purified. Caffeine Citrated is a cerebral and respiratory stimulant used primarily to treat idiopathic apnea of premature infants. Blood levels of caffeine in patients were determined to be significantly lower than would be expected. The use of sub-potent compounded preparations may lead to sub-therapeutic caffeine blood levels and an unacceptable risk of respiratory depression. Customers should examine their inventory, discontinue dispensing and using the product, quarantine the referenced lots of the product, and call the manufacturer to arrange to return the product for credit or replacement.

Read the complete 2007 Safety Summary, including a link to the Manufacturer's Recall Quick Facts Sheet and Customer Survey regarding this issue at: www.fda.gov/medwatch/safety/2007/safety07.htm#Caffeine

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Rhonda Byrne
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This 198-page, beautifully illustrated book is based on the legendary movie The Secret, available on DVD or for download at www.thesecret.tv. So what is the secret you ask? The Secret is plain and simple�it is the law of attraction. Teachings of this Great Secret have been found in the oral traditions, literature, science, religion, and philosophies throughout the centuries. Read the complete review for it and dozens of other books at www.CompoundingToday.com/Books/ReviewList.cfm

This week 51 citations and abstracts on the topics of DHEA supplementation (21) and erectile dysfunction (30) have been added to CompoundingToday.com's literature search database.

Better Capsules by Uniform Particle Size
One final tip on preparing capsules-capsules are filled by volume, not by weight. In other words, the capsule will hold a certain volume of powder when full. We convert that to weight through a trial-and-error system in determining how much "filler" to add to make the capsules "full" by volume, and they will weigh a certain amount. If the powder particles are not of relatively uniform size, during the encapsulation process, the smaller particles can fill in between the voids of the larger particles and these capsules may weigh "heavier" than others, as there is actually more powder encapsulated. Therefore, uniform particle size powders will result in better capsules with closer tolerances.