US Pharm. 2012;37(7):45-46.
Method of Preparation: Calculate the quantity of each ingredient for the amount to be prepared. Accurately weigh or measure each ingredient. Mix the testosterone with the silica gel, followed by the stevia powder extract. Melt the polyethylene glycol (PEG) 1450 (or PEG troche base) and heat to about 50°C to 55°C. Slowly sprinkle the powders onto the melted base and thoroughly mix. Add flavor, mix well, pour into molds, and allow to cool. Package and label.
Use: Testosterone troches are used for hormone replacement therapy (HRT) and for treatment of low libido.
Packaging: Package in tight, light-resistant containers.
Labeling: Shake well before taking. Keep out of the reach of children. Discard after ____ [time period].
Stability: A beyond-use date of up to 6 months may be used for this preparation.1
Quality Control: Quality-control assessment can include weight, specific gravity, active drug assay, color, texture of surface, appearance, feel, melting test, dissolution test, physical observation, and physical stability.2
Discussion: Testosterone is used for HRT in males, and also (in lower doses) to treat low libido in females. It occurs as white or slightly creamy-white crystals or crystalline powder that is odorless and stable in air. Testosterone is practically insoluble in water, soluble 1 g in 5 mL of ethanol and 100 mL of ether, and soluble in vegetable oils. It melts at 153°C to 157°C. Testosterone is subject to photodegradation in the presence of light. It is not very bioavailable when given as an oral-swallow preparation, but it is absorbed when administered buccally and sublingually. The different esters of testosterone are hydrolyzed to free testosterone, and subsequently are metabolized in the same way as testosterone itself. Testosterone is indicated for androgen replacement for delayed male puberty, postpartum breast pain and engorgement, inoperable breast cancer, and male hypogonadism.3,4
Stevia (honey leaf, yerba dulce) powder is a relatively new sweetening agent. It is the extract from the leaves of the Stevia rebaudiana Bertoni plant and is natural, nontoxic, and safe. Stevia occurs as a white, crystalline, hygroscopic powder. It may be used in both hot and cold preparations.5
Silica gel, a form of silicon dioxide, is obtained by insolubilizing the dissolved silica in sodium silicate solution. If the product is obtained by adding sodium silicate to a mineral acid, it is called silica gel, but if it is obtained by destabilizing a solution of sodium silicate to yield very fine particles, it is called precipitated silica. Silica gel occurs as a fine, white, hygroscopic, odorless, amorphous powder with a usual particle size of 2 microns to 10 microns. It is insoluble in water and alcohol and other organic solvents, but is soluble in hot solutions of alkali hydroxides. Silica gel is used as a desiccant, suspending agent, and viscosity-increasing agent.1,6
A mild flavor is suggested that will not excessively stimulate salivation and cause too-rapid dissolution and swallowing of the drug. Absorption through the oral mucosa will minimize the first-pass effect that results when the drug is swallowed and enters the systemic circulation from the small intestine, and so on.
PEG (Carbowax, polyoxyethylene glycol) is an addition polymer of ethylene oxide and water. The density of the solid PEGs ranges from 1.15 g/mL to 1.21 g/mL. The melting point for PEG 1000 is 37°C to 40°C, for PEG 1500 is 44°C to 48°C, and for PEG 1540 is 40°C to 48°C. The PEGs are soluble in water and miscible in all ratios with other PEGs. The solid PEGs are soluble in acetone, dichloromethane, ethanol, and methanol and are slightly soluble in aliphatic hydrocarbons and ether; they are, however, insoluble in fats, fixed oils, and mineral oil. The PEGs are chemically stable, do not support microbial growth, and do not become rancid.7
PEG troche base may be prepared using PEG 1000 (10 g), aspartame sweetener (20 packets), and flavor and food color as desired. Alternatively, a commercial product may be used.8
REFERENCES
1. U.S. Pharmacopeia 35/National Formulary 30. Rockville, MD: U.S. Pharmacopeial Convention, Inc; 2012:344-350,350-386,1144.
2. Allen LV Jr. Standard operating procedure for performing physical
quality assessment of suppositories, troches, lollipops and sticks. IJPC. 1999;3:56-57.
3. American Society of Health-System Pharmacists. AHFS Drug Information 2012. Bethesda, MD: American Society of Health-System Pharmacists; 2012:3109-3116.
4. Brunton L, Chabner, B, Knollman B. Goodman & Gilman’s The Pharmacological Basis of Therapeutics. 12th ed. New York, NY: McGraw-Hill Medical; 2011:1199-1207.
5. Reynolds JEF, ed. Martindale: The Extra Pharmacopeia. 37th ed. London, England: Pharmaceutical Press; 2011:2337-2342.
6. Hapgood KP. Colloidal silicon dioxide. In: Rowe RC, Sheskey PJ, Quinn ME, eds. Handbook of Pharmaceutical Excipients. 6th ed. London, England: Pharmaceutical Press; 2009:185-188.
7. Wallick D. Polyethylene glycol. In: Rowe RC, Sheskey PJ, Quinn ME, eds. Handbook of Pharmaceutical Excipients. 6th ed. London, England: Pharmaceutical Press; 2009:517-522.
8. Allen LV Jr. The Art, Science, and Technology of Pharmaceutical Compounding. 3rd ed. Washington, DC: American Pharmacists Association; 2008:162.
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