Prelab 6 Presented by Mai Tawfik Pharmaceutics I Prelab 6 Presented by Mai Tawfik

Prelab contents 1. Preparations Heavy magnesium oxide suspension . Black draught (infusion). Decoction . 2. Problems Dose calculations Percent preparation Percent error

Heavy magnesium oxide suspension Rx Heavy magnesium oxide ჳii Magnesium sulphate ჳvii Glycerin ჳi Acacia mucilage ℥i Peppermint water ad ℥iii Fiat: mist. Sig.: m.d.s. 2x4=8 g 7x4=28 g 1x4=4ml 1x30=30ml 3x30=90ml Laxative and antacid. Saline purgative Wetting agent Suspending agent vehicle Use: Laxative

3-add Mg oxide 4- mix the two powders together 5-add glycerin and levigate 1-grind MgSo4 with pestle 8-Rinse the mortar with small portion of peppermint water 9-Adjust volume to 90ml with peppermint water. 6-add acacia mucilage portion wise with levigation 7- Transfer to cup measure.

Label Fiat: mist. Sig.: m.d.s. Shake The Bottle The Mixture To be taken as directed.

Infusion preparation Black draught Rx Magnesium Sulphate 250 gm Compound tincture of cardamom 100 ml Aromatic spirit of ammonia 50 ml Fresh infusion of senna to 1000 ml Fiat :mist–send 100 ml Sig : 30 ml O.m. 25 gm 10 ml 5 ml 100 ml Saline laxative. Carminative. Antacid and carminative. Irritant laxative. F = required / prescribed = 100/1000 = 0.1 Use: purgative in chronic constipation.

Procedure: Prepare 120 ml of 5 % senna infusion ?? 5% Senna infusion means 5 g 100 ml ?? 120 ml 6 g senna Boil 120 ml H2O in kettle or flask and funnel. Then remove from flame. Crush 6 g of senna leaves and add to the boiled water. Leave for 15 min with occasional shaking (keep the kettle beside the flame and keep it covered). Filter on small wet piece of cotton (Don’t press it).

Procedure : 2) Transfer 50 ml of the infusion to a cup measure 3) Dissolve MgSO4 in the infusion while warm.

4) Cool then add tincture of cardamom and ammonia spirit 4) Cool then add tincture of cardamom and ammonia spirit. 5) Adjust the volume to 100 ml with cold infusion

The Mixture One coffeecupful to be taken every morning. The label: Fiat :mist Sig : 30 ml O.m. Shake The Bottle The Mixture One coffeecupful to be taken every morning.

Tincture Hyoscyamus 2 ml Spirit chloroform 0.5 ml Decoction Rx Potassium citrate 1 g Tincture Hyoscyamus 2 ml Spirit chloroform 0.5 ml Decoction of ammi visnaga (1/40) to 30 ml Fiat: Mistura Sig: ℥i t.d.s. p.c. X 3 3 g 6ml 1.5 ml 90 ml Mitte: III doses Factor = 3 Amount of decoction = 100 ml 1 g ammi visnaga  40 ml water x g  100 ml water Amount of ammi visnaga = 2.5 g 20% xss to compensate loss by evaporation = 100 + 20% xss = 120 ml

Use: Antispasmodic in renal colic Rx Potassium citrate Tincture Hyoscyamus Spirit chloroform Decoction of ammi visnage (1/40) Fiat: mistura Mitte: III doses Sig: ℥i t.d.s. p.c. Preparation: Use: Antispasmodic in renal colic BOIL 120 ml WATER + 2.5 g Ammi visnaga Shake The Bottle After start of boiling LOWER the flame Leave for 15 minutes ON FLAME The Mixture One coffeecupful to be taken three times daily after meals. COOL to 400C Filter on cotton Dissolve K citrate while WARM Transfer ½ decoction to cup measure COOL PRESS COTTON COMPLETE VOLUME to 100 ml in cup measure Add spirit chloroform Add tincture hyoscyamus Complete final volume with decoction COLD

TAKE CARE!!!!!!!!!!!! If amount of water is lost during boiling ADD water to prevent charring of the drug. All preparations containing plant extracts as decoction & infusion should be labeled “Shake The Bottle”

TAKE CARE!!!!!!!!!!!! Boil Water with ammi visnaga Active ingriedients here not heat-senstive Cool before filteration Y? To reprecipetate unwanted substances that dissolved during boiling then filter. Why press the cotton? Because albuminous matter coagulated by boiling and will not pass so no turbidity.

Decoction Infusion Boil Water with ammi visnaga for 15 min. Boil Water only and add senna leaves to water after boiling Cool before filtering. Don’t cool before filtering. After filtration press the cotton After filtration Don’t press the cotton After filtration complete volume to 100 ml in cup measure to replace water lost by evaporation. After filtration Don’t complete volume (to avoid dilution) Calculate for 20% excess water to guard against loss by evaporation during boiling Calculate for 20% excess infusion to guard against loss by filtration. Used for heat stable drugs.Ex: woody plants or seeds (as ammi visnaga) Used for heat sensitive drugs. Ex: leaves (as senna leaves).

CALCULATION of DOSES Label Sig. One teaspoonful 5 ml Ʒi One tablespoonful 15 ml ℥ss One coffeecupful 30 ml ℥i One wineglassful 60 ml ℥ii

CHILDREN DOSE Young’s rule  CHILD DOSE = Cowling’s rule  CHILD DOSE = Fried’s rule  CHILD DOSE = Clark’s rule  CHILD DOSE = Using BSA (body surface area)  CHILD DOSE =

NOMOGRAM

% Preparation Percent weight-in-volume (%w/v): expresses the number of grams of a constituent in 100 ml .of solution or liquid preparation Percent volume-in-volume (%v/v): expresses the number of milliliters of a constituent in 100 ml. of solution or liquid preparation Percent weight-in-weight(%w/w): expresses the number of grams of a constituent in 100 g. of solution or liquid preparation.

The term % used without qualification means……?? for solutions or liquid preparations (solid in liquid) % w/v for solutions of liquids in liquids % v/v for mixtures of solids % w/w for solutions of gases in liquids

Milligrams percent (mg%) : Expresses the number of. milligrams of a substance in 100 ml. of solution It is used frequently to denote the concentration of a drug or natural substance in a biological fluid, as in the blood. Parts per million (ppm): For very dilute solutions e.g.in designating test limits The limit of arsenic in zinc oxide is 6 parts per million (6 ppm) or 0.0006%.

N.B 1% solution is prepared by dissolving 1 g of a solid or 1 ml of a liquid in sufficient of the solvent to make final volume of the solution is 100 ml.

Ratio strength It is a ratio the first figure of which is 1 It is anthor way of expressing concentration For example 5% means 5 parts per 100 5 : 100 1:20 It is a ratio the first figure of which is 1

When a ratio strength 1 :1000 is used to designate conc When a ratio strength 1 :1000 is used to designate conc. , it is interpreted as : 1) For solids in liquid: 1 gram of solute or constituent in 1000 milliliters of solution or liquid preparation, or 1 grain of solute or constituent in a volume of solution or liquid preparation represented by that of 1000 grains of water. 2)For liquid in liquids: 1 milliliter of constituent in 1000 milliliters of solution or liquid preparation, or 1 minim of active ingredient in 1000 minims of solution or liquid preparation. 3)For solids in solids 1 gram of constituent in 1000 grams of mixture or 1 grain of active ingredient in 1000 grains of mixture.

Examples (1) Express 0.02% as a ratio strength 0.02 → 100 0.02 → 100 1 → x ⇨x= 1 x 100/0.02 = 5000 ∴ Ratio strength = 1 : 5000 (2) Express 1 : 4000 as a percentage strength 1 → 4000 x → 100 ⇨ x = 100 x 1/4000 = 0.025% ∴ % strength = 0.025 %

Percentage of error % error = ( error / quantity desired) x 100 N.B. error and the quantity desired are expressed in the same denomination. Example: When the maximum potential error is ±4 milligrams in total of 100 mg what is the percentage of error? Anwer: (4/100) x 100% = 4 %

When certain % of error is not to be exceeded and the maximum potential error of a balance is known the smallest quantity that can be weighed is calculated from this equation : Smallest quantity =(max. potential error/permissible % error) x100

Smallest quantity =(max. potential error/permissible % error) x100 Quantity measured error Quantity measured= x 100 % error If the quantity increases % error decreases If quantity decreases %error increases

Example: What is the smallest quantity that can be weighed with a potential error of not more than 5% on a balance sensitive to 6 milligrams? Answer: (100 x 6) / 5 =120 mg

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