FAQ 7: METHODS OF USE-PLO GEL *MUST READ*
The following explanation on "Everything Plo Gel" is brought to us by Fafhrd. The following also happens to be for educational purposes ONLY. MASSLIFTER
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EVERYTHING YOU NEED TO KNOW ABOUT PLO GEL
OVERVIEW:
PLO gel 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 characteristics
soy lecithin – complex mixture of phospholipids and other materials. Used as dispersing, emulsifying and stabilizing agents.
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 PLO'S 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.../art-1401.04htm
PLO 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 PLO GEL:
The kit contains the following:
1 – 10 ml syringe containing 5 mls of alcohol based solvent.
1 – 60 ml syringe containing 11 mls of component “A”.
1 – 60 ml syringe containing 34 mls of component “B”. (Place component “B” in the refrigerator until ready to use. This will cause it to liquefy).
1 – 1 ml oral syringe
1 – red luer lock
1 – white luer lock
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!
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
