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

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

3. Heavy magnesium oxide suspensionRx
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

4. 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.

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

6. Infusion preparation Black draughtRx
Magnesium Sulphate gm
Compound tincture of cardamom ml
Aromatic spirit of ammonia ml
Fresh infusion of senna to 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.

7. Procedure: Prepare 120 ml of 5 % senna infusion ??
5% Senna infusion means
5 g ml
?? 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).

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

9. 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

10. 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.

11. Tincture Hyoscyamus 2 ml Spirit chloroform 0.5 ml
Decoction Rx
Potassium citrate g
Tincture Hyoscyamus ml
Spirit chloroform 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 = % xss = 120 ml

12. Use: Antispasmodic in renal colicRx
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 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

13. 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”

14. 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.

15. 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).

16. 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

17. 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 =

18. NOMOGRAM

19. % 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.

20. 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

21. 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 %.

22. 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.

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

24. 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.

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

26. 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 %

27. 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

28. 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

29. 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

30. Thank you