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EVERYTHING YOU NEED TO KNOW ABOUT PHLOJEL
PHLOJEL or pluronic lecithin organogel is a transdermal carrier used by
compounding pharmacists to deliver NSAIDS,narcotics and other drugs through the
skin when other routes of administration are not viable. PLO gel is similar to
the system used in the testosterone preparation Androgel. PLO gel is
non-irritating to the skin, absorbs quickly and is practically odorless. It is
best used with drugs with molecular weights less that 400.
It is a two phase system consisting of an oil (lipophilic) phase and a water
(hydrophilic) phase. Oil soluble drugs are dissolved in the oil phase and water
soluble drugs are dissolved in the water phase. One phase is injected into the
other, back and forth until a smooth homogeneous gel is formed. The preferred
method of mixing small batches is with the use of two large syringes locked
together at the tips
PLO GEL CONSISTS OF THE FOLLOWING:
isopropyl palmitate - a non-oleaginous emollient with very good spreading
soy lecithin - complex mixture of phospholipids and other materials. Used as
dispersing, emulsifying and stabilizing
H2O
Pluronic F127 - a long chain polymer that has the unique property of being a
solid at room temperature. This characteristic makes it useful in that it can be
drawn into a syringe for accurate dose measurement when it is cold. When it
warms on the skin it thickens to the perfect consistency to facilitate proper
inunction and adhesion.
BARRIERS IN THE SKIN:
To fully understand how a PLO works, it is important to first understand the
barriers in the skin, which prevent absorption into the skin. The skin is
composed of three major components: the epidermis, the dermis, and the
underlying subdermal tissue. The epidermis, which provides the strongest
protection against drug absorption, is composed of five different layers:
stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum and
stratum basale. Of these five layers, the stratum corneum is the most
impermeable. The stratum corneum can be compared to a brick wall. Just as a
brick wall consists if bricks and mortar, the stratum corneum consists of
flattened, cornified cells imbedded in a lipid intercellular matrix.
HOW PHLOJEL WORK
Two mechanisms have been proposed. One possible mechanism for gel permeation
into the skin occurs by diffusing through the lipid intercellular matrix
described above. Another proposed mechanism is that the PLO provides a slight
disorganization of the skin allowing permeation of the gel and the active drug
through the statum corneum. One thing that is clear is that the lecithin
component of the PLO has the ability to act as an amphoteric surfactant and
enables many drugs to penetrate the dermal layer
BIOAVAILABILITY:
In the past, topicals have had relatively poor bioavailability. With the advent
of the PLO the problem of bioavailability has been somewhat resolved. The PLO
provides an adequate vehicle that permeates the stratum corneum, thereby
increasing the amount of available drug. Because lecithin is a lipophilic
substance, it is able to pass through the stratum corneum. When a water-soluble
drug is added to a hydrophobic substance, with the aid of a surfactant, both the
drug and the hydrophobic medium can pass through the epidermis. Bioavailability
ranges from 10 % to 60%. I strongly recommend that you read the following study.
It compares test gel to test injection and, in the absence of a study using
Fina, is one of the best references available:
www.familypractice.com/journal/2001/v14.n01/1401.04/art-1401.04htm
PHLOJEL AND FINA
If using gel to apply Fina, good results can be had with as little as 40 mgs per
day when stacked with at least 250 mgs/week of testosterone. I would always
stack Fina with test whenever possible. When using Fina only, the dose needs to
be bumped up to 80-160 mgs per day in two or three equal applications. It should
be applied to a clean, hairless part of the body. Inside of forearms and upper
chest work well. The PLO gel forms sort of a depot in the skin that provides
sustained release of the drug.
There have been reports of increased photosensitivity with plo gel so you should
stay out of the sun after application, or apply to an area that will be covered,
such as the inside of the upper thigh.
TUTORIAL FOR MIXING FINA WITH PHLOJEL
The kit contains the following:
1 - 10 ml syringe containing 5 mls of alcohol based
1 - 60 ml syringe containing 11 mls of component
1 - 60 ml syringe containing 34 mls of component. (Place component in the refrigerator until ready to use. This will cause it to
1 - 1 ml oral
1 - red luer
1 - white luer
Directions for use:
Place 2000 mg (2 grams) of pellets in the 10 ml syringe containing the solvent
as follows:
Hold syringe so that the red tip is pointed up. Loosen the tip and pull back the
plunger until it catches on the indent allowing air into the syringe. Tighten
the tip. Invert the syringe so that the red tip is pointed down. Gently pull the
plunger all the way out. Be careful not to spill! Add the pellets. Replace the
plunger past the indent. Invert the syringe so that the red tip is pointed up
again. Loosen the tip and depress the plunger to purge about half the air.
Tighten the tip. This leaves room to shake contents. Let sit overnight shaking
occasionally or until completely dissolved. The solution will have separated
into a clear golden top layer and a yellow suspension on the bottom. Shake
thoroughly. Some small solids are OK as long as they will pass through the end
of the syringe. Point the tip up and remove the cap.
Depress the plunger until all the air is purged and the solution just starts to
come out. Replace the cap. Set the �A� syringe on its plunger and remove the
red cap. Gently screw the red luer lock on the tip of the �A� syringe. Purge
any air in the �A� syringe by gently pulling down on the syringe (not the
plunger) until solution just starts to come out. Take the cap off of the 10 ml
syringe and gently screw it onto the other end of the red luer lock. Gently
depress the plunger on the 10 ml syringe until all of the solution has been
injected into compound �A�. Remove the 10 ml syringe
Purge the air from the �B� syringe the same way. The goal is to not let any
air into the system. You are making a gel not a mousse. Gently screw the 60 ml
syringe with component �B� onto the other end of the red luer lock. Depress
the plunger on the �A� syringe, injecting the contents into the �B�
syringe. Reverse and inject the contents of the �B� syringe into the �A�
syringe. Repeat (at least 10 times) until you have a homogeneous pale yellow
gel. You now have 50 mls of a 4% gel by weight.(40 mgs/ml) Remove the empty
syringe.
Remove the red luer lock from the full syringe. Attach the white luer lock to
the full syringe (Be sure to use threaded end). Remove the cap from the 1 ml
syringe and press it onto the other end of the white luer lock. While pressing
the 60 ml syringe, pull on the 1 ml syringe, and fill the 1 ml syringe to .625
mls. Keep a loose grip on the 1 ml syringe. It has been known to pop out under
pressure and decorate the ceiling with gel. Remove the 1 ml syringe and apply
gel to a clean body part (delts, abs, thighs). Rub gently until gel is
completely absorbed (about 1-2 minutes). Skin will be slightly tacky. This
disappears in about 5 minutes. Each ml contains 40 mgs of active ingredient.
.625 ml applied twice daily provides 50 mgs per day and lasts for 40 days.
Adjust dosage to the individual. Do not refrigerate the gel! This
will cause the two components to separate.
*CAUTION! KEEP AWAY FROM EYES!*
Congratulations and good luck!
OVERVIEW: Written by Fahfred
Thanks to Jim Franckum and Dale Ramsay
BIBILIOGRAPHY
Ansel, Howard, C., Allen, Loyd V., Ropovich, & Nicholas G. Jr. Dosage Forms
and Drug Delivery Systems, Philadelphia 1999
Berti, Jerrfey J., & Lipskys, James J. Transcutaneous Drug Delivery: A
Practical Review, Mayo Clin. Proc. 1995; 70:581-586
Gans, John A. & Kerscher, Robert D., Drug Information Handbook 1998-1999,
LexiCorp Inc., Hudson, Ohio
Guyton, Arthur C., & Hall, John E. Textbook of Medical Physiology Ninth
Edition, W.B. Saunders Company 1996, Philadelphia
Willimann, P Walde, Luisi, P.L. Gazzaniga, A., & Stroppolo, F. Lecithin
Organogel as Matrix for Transdermal Transport of Drugs, Journal of
Pharmaceautical Sciences: Vol 81, No 9, Sept 1992, 871-874
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