DISPENSING LAB NOTES Rx 1 - 13
Egr
Parts of a Prescription 1. Patient’s Info 2. Superscription
Methods of Preparation: a. Weighing – most accurate; for potent substances b. Block and Divide
Rx symbol – “recipe”, “take thou” 3.
Inscription a. Basis –
PRESCRIPTION NO. 1A: SALICYLIC ACID FOOT POWDER
active
ingredient
serves
as
basis
for
prescription Adjuvant – serves to aid the basis Corrective – used to correct undesirable properties of
b. c.
the basis
Therapeutic Use: Antifungal Route of Administration: Topical/External INGREDIENT
PHYSICAL CHARACTERISTICS
SOLUBILITY
USE
Salicylic acid
White crystals usually fine needles/fluffy white pwdr
Sol. in alcohol, slightly sol. in water
Dermatological problems; analgesic
Benzoic Acid
White flakes
Camphor
White crystals
Insol. water
– intimate mixture of dry finely divided drugs or substances that maybe intended for internal use
Menthol
Waxy, clear white crystalline subs.
Slightly sol. in water
Types of Comminution: a. Trituration – use of mortar and pestle; grinding motion b. Pulverization with Intervention – use of mortar and
Phenol
pestle; addition of solvent (ex. camphor and alcohol) addition of non-solvent/levigating agent to form a paste Mills and Pulverizer – for large production
White or clear acicular crystals
Starch
Irregular, angular white masses or fine pwdr
4. 5. 6.
d. Vehicle Subscription – instruction to the pharmacist Transcription – “signa”, instruction to the patient Prescriber’s Info
Beyond Use Date: 1. For non-aqueous liquids and solids – not later than 25%
2. 3.
of the time remaining until product’s expiration or 6 months, whichever is less For water containing drugs – 14 days at cool temperature Others – intended duration of therapy or 30 days; whichever is less
POWDERS
c. d.
Levigation -
crystalline
Topical Antiseptic in Antimicrobial
Cooling effect
Antiseptic
Insol. in cold water and alcohol
Filler, Binder
Blending Techniques: a. Spatulation –
used to blend eutectic mixtures or substances that liquefy
b. c.
Trituration Geometric dilution – used to blend potent substances;
d.
Sifting – use of a sieve; results to fluffy powder; for non-
e.
potent materials Tumbling – for large scale production
diluent is added portion by portion
Types of Powders: A. Bulk Powder • • • • •
B.
Dusting powder Used in bulk No specific dosage strength For internal (antacids) – wide mouth bottle For external use – sifter bottle
Divided Powder • •
With controlled dosage Also called paper tabs, chartulae, powder paper
Types of Paper Used: a. Simple Bond Paper
-
No moisture resistance Opaque
b. Vegetable b. Vegetable Parchment
-
Onion skin, thin semi-opaque paper With limited moisture resistance
Procedure: 1. Triturate camphor, menthol and phenol. 2. Add salicylic acid then benzoic acid. 3. Add starch, portion by portion. 4. Pass through sieve #40. Incompatibility: Eutectic Mixture of Camphor and Menthol Remedy: Add phenol.
PRESCRIPTION NO. 1B: CAMPHOR FOOT POWDER
Therapeutic Use: Antifungal Route of Administration: Topical/External INGREDIENT PHYSICAL SOLUBILITY CHARACTERISTICS Calamine powder
Pink pwdr
Camphor
White crystals
Talc
Very fine, white crystalline pwdr
Starch
Irregular, angular white masses or fine pwdr
c. Glassine
-
Transparent, frosted With limited moisture resistance
d. Waxed
-
Transparent Waterproof
USE
Antipruritic
Insol. in water
Antimicrobial Filler, diluent
Insol. in cold water and alcohol
Stabilizer, Filler, Binder
Egr
DISPENSING LAB NOTES: Rx 1 - 13 Procedure: 1. Triturate camphor in 1 drop of alcohol. (Pulverization with intervention) 2. Add calamine, starch and talc. 3. Pass through sieve #40. Computations: Camphor………………0.08 parts Calamine pwdr……..8 parts Starch………………….9.2 parts Talc…………………….30 parts
PRESCRIPTION NO. 4: SULFADIAZINE-ASPIRIN PAPER TAB
Therapeutic Use: Antibiotic Route of Administration: Oral
0.08 parts: total parts = x : 10 g 0.08 parts camphor : 47.28 parts = x : 10 g x = 0.0169 g camphor
Ingredients: Sulfadiazine Available in 500 mg tablet or 7.7 gr Antibiotic Sodium Bicarbonate Increases solubility of sulfadiazine Acetylsalicylic acid Antipyretic, Anti-inflammatory, Analgesic To prevent gummy mass or hydrolyzation of ASA, double wrap the prep.
8 parts calamine : 47.28 parts = x : 10 g x = 1.69 g calamine powder 9.2 parts starch : 47.28 parts = x : 10 g x = 1.95 g starch 30 parts talc : 47.28 parts = x : 10 g x = 6.35 g talc PRESCRIPTION NO. 2: Al –Mg BULK POWDER (INTERNAL USE)
Therapeutic Use: Antacid Route of Administration: Oral INGREDIENT
PHYSICAL CHARACTERISTICS
USE
Fine, white, tasteless pwdr
odourless,
Antacid
Peppermint oil
Fragrant
Calcium carbonate
Antacid, Adsorbent
Procedure: 1. Triturate aluminium hydroxide. 2. Add magnesium silicate 3. Add calcium carbonate 4. Add peppermint oil until desirable scent. 5. Mix. PRESCRIPTION NO. 3: SULFADIAZINE PAPER TAB
Therapeutic Use: Antibiotic Route of Administration: Oral Ingredients: Sulfadiazine Available in 500 mg tablet or 7.7 gr Antibiotic Sodium Bicarbonate Increases solubility of sulfadiazine Lactose Diluent – if amount of the AI is less than 2 gr or 130 mg Corrective – if amount of AI is greater than 2 gr or 130 mg As corrective, amount of lactose is equal to amount of the AI •
Procedure: 1. Triturate each ingredient separately. 2. Mix the powder by spatulation. Incompatibility: ASA and Sodium bicarbonate form a mass Remedy: Do not triturate. Use spatulation method. PRESCRIPTION NO. 5: CARBAMAZEPINE POWDER PACKET
Antacid
Aluminum hydroxide Magnesium trisilicate
Procedure: 1. Crush and triturate the tablet. 2. Add sodium bicarbonate and triturate. 3. Add lactose and triturate. 4. Block and divide.
Therapeutic Use: Anticonvulsant Route of Administration: Oral Ingredients: Carbamazepine Used as anticonvulsant Even in solid dosage forms, it has stability problems Decreased bioavailability caused by tablet hardening Should be kept in a tightly closed container because it becomes dehydrated when exposed to moisture, decreasing its bioavailability Recommended dose: 5 – 20 mg/kg.day Lactose Diluent Procedure: 1. Triturate carbamazepine tablet and put in 30 mg packet. 2. Add lactose to make 300 mg. 3. Weigh to check final weight. Computations: Carbamazepine 100 mg/powder packet 100 mg carbamazepine + diluent (lactose) = 300 mg powder packet Diluent = 200 mg lactose 100 mg packet = 100 mg/dose Sig.: Take 1 pwdr packet q.i.d, p.c. & h.s. Determine the prescribed dose (mg/kg/day) a. 35 lbs patient 35 lbs x 1kg/2.2 lbs = 15.91 kg 100 mg/dose x 4 doses per day = 400 mg/day 400 mg per day / 15.91 kg = 25 mg/kg/day ! OVERDOSED Amount of carbamazepine : 30 mg per packet Available strength: 200 mg/tab Ave wt./tab = 280 mg 200 mg : 280 mg/tab = 30 mg per packet : x x = 42 mg crushed carbamazepine powder per packet
Egr
DISPENSING LAB NOTES: Rx 1 - 13 PRESCRIPTION NO. 6: ANALGESIC CAPSULE PRESCRIPTION NO. 7: GELATIN PASTILLES
Ingredient
Amount
Pharmaceutical Use Ingredient
Phenylsalicylate/Salol
0.325 g
ASA
0.163 g
Antipyrine
0.163 g
Amount
Computed Amount to make 5 pastilles
Pharmaceutical Use
Gelatin
1.0 oz
4g
Emulsifying agent
Glycerin Acacia Aromatic water/Peppermint water Color, q.s
2.5 oz. 2.0 oz 2.0 oz
2 mL 2g 2 mL
Solvent Demulcent Carminative and flavoured vehicle
Antiseptic
Analgesic, Antipyretic, Anti-inflammatory
Analgesic
M. Ft. cap no. 24 Sig. One capsule every 12 hours.
Colorant
M. Ft. Pastilles Sig. One pastille when needed.
Physical Incompatibility: Eutectic mixture of Phenylslicylate & Aspirin: Disperse separately. Eutexia – when 2 components are mixed together that would eventually liquefy. Eg. Camphor, Menthol, Thyrol * ASA forms a damp pasty mass with antipyrine Remedial measures: -addition of adsorbent -Superimposition -Disperse separately Method of preparation 1. Superimposition 2. Cap 0: ASA, Antipyrine 3. Cap 00: Salol Compounding Procedure: 1. Triturate powders separately 2. Place antipyrine in the SMALL capsule 3. Place adsorbent layer 4. Add ASA in the SMALL capsule 5. Introduce salol in the BIG capsule and place small capsule inside
Compounding Procedure: 1. Triturate gelatin and acacia. 2. Mix the gelatin and acacia. 3. Add 2 m L of glycerine. 4. Add peppermint water. 5. Form into pastilles.
Route of Administration: Oral •
GELATIN
-Stable in air when dried -subject to microbial decomposition when moistened or in solution -suppository vehicles •
ACACIA
-demulcent in the throat or stomach •
GLYCERIN
-1.249 density -preservative property -humectant
Capsule Sizes •
PEPPERMINT OIL
-menthol -flavoring, carminative, antiseptic, local anes. •
Aromatic Water
-Cleared saturated aqueous solution of volatile oils which are medicated in nature. •
•
Peppermint has a digestive property, antinausea and refreshing that is why it is an ideal flavorant for mouth and throat preparations. Beyond use date: One month after prep
Egr
DISPENSING LAB NOTES: Rx 1 - 13 •
Ingredient
Amount
Pharmaceutical Use •
Quinine sulfate
gr X
SYRUP NF
-sweetener -preservative -vehicle -flavorant
Anti - infectives
M. Ft. pill no. X Sig. One pill twice a day.
SORBITOL 70%
-suspending agent -sweetener -vehicle
PRESCRIPTION NO. 8: QUININE SULFATE PILLS
•
Beyond use date: 14 days after prep
PRESCRIPTION NO. 10: DEXTROMETHORPHAN LOZENGES
Route of Administration: Oral HARD LOZENGES •
QUININE SULFATE
-Anti-Malaria -darkens on exposure to light -600mg every 8hours • •
• •
•
•
Use geometric dilution Advantage of Pills: Suitable for Extemporaneous Compounding Disadvantage of Pills: Does not mask the taste well Beyond use date: 14 days after prep
•
Solid syrups of sugars made by heating sugar with other ingredients and pouring the mixture in the mold Will not disintegrate in the mouth but will erode or dissolve over 5-10 min period Requirement: low moisture content (.5-1.5%)
INGREDIENT
AMOUNT PER DOSE
Powdered Sugar
2.1 g
Light Corn Syrup
0.8 mL
Binder
Puriified Water
1.2 mL
Wetting Agent, Vehicle
Dextromethorphan
5 mg
Antitussive
Mint Extract
0.06 mL
Flavoring Agt
Anti-infectives
Food Color
qs
Colorant
Sweet vehicle
M ft. 10 lozenges
Sweet vehicle
Compounding Procedure
PRESCRIPTION NO. 9: NYSTATIN POPSICLE
Ingredient
Nystatin
Amount
Computed Amount for 2 popsicles
2,000,000 units 10 mL
4 mL
Sorbitol 70% 2 mL Solution USP Syrup NF 30 mL 6 mL Purified 100 mL 20 mL Water, qs ad M. et Div. to make #10 popsicles Sig. Eat one popsicle every 8 hours for thrush.
Pharmaceutical Use
Compounding Procedure: 1. Mix sorbitol, syrup and water. 2. Add 3 grams of gelatin, portion by portion. 3. Add nystatin. 4. Heat to dissolve the powders. 5. Seal using aluminium foil. 6. Put popsicle stick when half-frozen. Route of Administration: Oral •
NYSTATIN
-Antifungal -100,000units, 4x a day -pH: 4.5 -7
USE
1. 2. 3. 4. 5. 6. 7. 8.
Vehicle, sweetener
Combine sugar, corn syrup and water in a beaker and stir until mixed well Cover the mixture & heat on a hot plate at high setting until the mixture boils & continue boiling for 2 mins Uncover and remove from heat at 1410C Do not stir the mixture until the temp is 1290C Quickly add the AI, mint extract, food color and stir until well mixed Put small amounts of vegetable oil to the mold Pour the melt into the molders Cool, package and label
Egr
DISPENSING LAB NOTES: Rx 1 - 13 SUPPOSITORIES •
solid dosage forms intended for insertion into the body orifice where they melt, soften, dissolve & exert localized and systemic effect
•
Local – 1/3 upper portion of the rectum
•
Systemic – 1/3 lower portion of the rectum
Rectal - cylindrical, bullet shape; 32 mm (1
Computations: Aspirin … 100 mg 100 mg x 8 suppositories = 800 mg or 0.8 g ! inch),
2
grams (adult) or 1g (children) 2.
aspirin will displace 1 g of cocoa butter) Example: M. ft. suppositories #6 (+2 extra) = 8
Types
1.
Recommended pediatric dose: 10-15 mg/kg/day Displacement value/Density factor of Aspirin = 1.1 (1.1 g of
1.1 g of ASA : 1 g of cocoa butter = 0.8 g of ASA : x x = 0.73 cocoa butter Average weight of cocoa butter = 1.72 g* x 8 = 13.76 g – 0.73 g of cocoa butter = 13.03 g of cocoa butter for 8 suppositorites (* average weight per suppository)
Urethral – slender or pencil shape
Male- 4 g 140mm (length) 3-6 mm diameter Female- 2g 170mm (length) Use: dilatation of utherus, anti-infective agent, erectile dysfunction
MEDICATION STICKS •
3.
Vaginal – globular, oviform, coreshaped; 5g; anti-fungal,
•
anti-infective, contraceptive
convenient forms for administering topical medications different sizes and shapes for application to different areas of the body
Desirable Characteristics
Spreads easily without excessive - greasiness • Does not sweat, crumble or crack • Uniform, stable, and free from mottling
•
Suppository Bases
1. Cocoa Butter – Theobroma oil, most widely used
Bases 1. Melting bases – soften at body temperature and spread the
2. Witepool bases – Contains natural saturated fatty acid chain between C12 and C18 - Lauric acid
drug-vehicle mixture over the skin a. Opaque – waxes, oils, PEGs b. Clear - sodium stearate/glycerin mixtures *if waxes and oils or plain polymers (PEGs) alone are used – topical effect
3. Wecobee base – derived from coconut oil
3.
PRESCRIPTION NO. 11: ASPIRIN SUPPOSITORIES
Ingredient
Amount
Pharmaceutical Use
Moisten bases - solid sticks which must be moistened to
become “activated” - concentrated solution of the drug will be present at the tip of the stick and, when applied, will exert its effect topically *Some ingredients added:
Aspirin
100 mg
Cocoa butter
q.s.
Analgesic, Antipyretic, Antiinflammatory
Valuable for suppositories
Vitamin E and A - emollient and skin enhancement effects • Zinc Oxide, PABA, - sun block • Perfume oil - perfume sticks
making
Compounding Procedure
1. Weigh the AI and triturate in a mortar. 2. Reduce cocoa butter to smaller pieces. 3. Carefully heat a small portion of the base in a beaker on a warm water bath until the base has turned to a fluid (approximately 55˚C water bath). 4. Add the AI to the melted base and stir. 5. Add the remainder of the base in portion with stirring. 6. Pour the molten mixture into the frozen molder. 7. Allow the suppository to congeal. 8. Trim the excess material from the top of the mold using spatula 9. Carefully remove the suppository from the mold cavities.
Categories of Medication Stick (with sample formulations) 1. Soft-opaque
Egr
DISPENSING LAB NOTES: Rx 1 - 13 2.
OINTMENTS
Soft Clear
Ointment/Salve/Charisma – Semi-solid preparation intended for external application application to skin and mucous membrane Characteristics 1. Free from grittiness 2. Becomes rancid with time 3. Easily spread 3.
Hard
Uses 1. Emollient –skin pliable 2. Protective barrier 3. Vehicle – for medication Pacakging 1. Jars – get ointment from the surface, do not dig for it will leave greater surface area exposed - ! Rancidity and growth of bacteria 2. Tubes - More preferred, less exposure
Counseling
Apply only to the involved area and not to surrounding skin • Apply liberally over the area • Apply as needed. • Clean the surface of the stick with clean tissue after use • Do not share this product with others because of the possibility of transmitting infections •
PRESCRIPTION NO. 12: MEDICATED STICK
Methyl salicylate Menthol Sodium stearate Propylene glycol Purified water
5.5 g 1.5 g 1.3 g Stiffening Agent 2.5 g 1.2 g
4 Types of Ointment Bases
Dispense 5 g medication stick. Sig. Apply to painful areas of right elbow and ar m t.i.d. prn pain.
1. Oleaginous Base – Example: petrolatum, synthetic ester, lanolin derivative
PROCEDURE:
2. Absorption Base – Example: hydrophilic petrolatum, woolfat (anhydrous lanolin)
1. Weigh/measure the ingredients. 2. Gently heat and melt the Sodium Stearate. 3. Mix the Purified Water with the Propylene Glycol and add to the melted Sodium Stearate.
3. Emulsion Base – Example: Hydrophilic ointment and vanishing cream (o/w); hydrous woolfat and cold cream (w/o) 4. Water Soluble base – Example: PEG, Propylene glycol
4. Mix thoroughly, remove from heat and allow this base to cool slightly. 5. Dissolve the Menthol in the Methyl Salicylate, add this solution to the base and mix thoroughly. 6. As the product begins to thicken, continue to mix and pour into 5 g stick containers. 7. Allow to harden at room temperature.
Methods of Preparation 1. Levigation – Use of mortar and pestle - Reduction to impalpable powder to reduce grittiness and to form a very smooth nucleus
Egr
DISPENSING LAB NOTES: Rx 1 - 13 2. Fusion – use of heat - Heat first the substance with high melting point like wax and spermaceti using water bath before adding soft, oleaginous material
PRESCRIPTION NO. 13A: BETAMETHASONE OINTMENT INGREDIENT
ORIGINAL AMOUNT
Betamethasone Diproprionate ointment
1g
PEG 400
2g
Distilled water
2g
Procedure 1. Levigate hydrocortisone powder with small hydrophilic petrolatum. 2. Geometrically incorporate the rest of petrolatum. 3. Add urea and paraben very gradually (6 g urea dissolve in 9 mL water + 3 g paraben/ PG) Remarks Weight of hydrocortisone Paraben or PG Urea Water
0.6 g 3.0 g 6.0 g 9.0 g_ 18.6g Weight of petrolatum= 60g-18.6g=41.4 g hydrophilic petrolatum
Urea - hard crystalline substance that is difficult to levigate to a fine powder; dissolve in water before incorporation into the ointment base 1g : 1.5mL water 6g x 1.5mL = 9 mL of water
Mitte 10 g Sig. Apply to affected area 2x a day.
White petrolatum - hydrophilic petrolatum - cannot absorb the water added
Procedure:
1.Triturate 1g Bethamethasone with PEG 400. 2. Add distilled water. 3. Place in a suitable container. Remarks:
Betamethasone Dipropionate Ointment- anti-inflammatory PEG - Water Washable, Soluble in Water, Absorb/Contain water
PRESCRIPTION NO. 13B: HYDROCORTISONE OINTMENT Ingredient
Original Amount
Hydrocortisone
0.6 g
Urea
6.0 g
White petrolatum, q.s. ad
60.0 g
Sig. Apply to affected area up to qid.
Hydrocortisone
0.6g
Anti-inflammatory, antipruritic
Paraben or PG
3 g
Preservative
Urea
6g
Mild keratolytic, hydrates skin
Purified water
9 mL
Solvent
41.4
Vehicle, emollient
Hydrophilic petrolatum
+ 3g preservative (due to the addition of water) Methyl paraben 0.2 % of weight of the ointment Propyl paraben 0.02 % Propylene glycol 2-3%
0.12g 0.012g
2.868g 3.000g
