Prelab 8

Alligation Problems Liquid Paraffin emulsion Turpentine oil emulsion

ALLIGATION

Alligation Medial Used to calculate the “Average Percentage Strength” of mixture of two or more substances whose quantities and concentrations are known.

What is the percentage of alcohol in a lotion containing 1500ml What is the percentage of alcohol in a lotion containing 1500ml. of witch hazel (14% alcohol), 2000ml. of glycerin, and 5000 ml. of 50% alcohol?

Alligation Alternate Percent desired Percent given Parts required Used to calculate the number of parts of two or more components of a given strength when that should be used to prepare a mixture of desired strength. Percent desired Percent given Parts required

a y c b x Number of parts of minus gives gives minus

Example In what proportion should alcohols of 95% and 50% strengths be mixed to make 270 ml 70% alcohol? 95 20 Number of parts of minus gives 70 minus gives 50 25 Number of parts of

In what proportion should 20% benzocaine ointment be mixed with ointment base to produce a 2.5% benzocaine ointment? 2.5 20% zero% 2.5% 17.5

100% 15% 10% 5 85 100% : 10% Parts 5 : 85 grams x : 3400g x= 200 g How many grams of zinc oxide should be added to 3400 g. of a 10% zinc oxide ointment to prepare a product containing 15% of zinc oxide? 100% 10% 15% 5 85 100% : 10% Parts 5 : 85 grams x : 3400g x= 200 g

A hospital pharmacist wants to use three lots of ichthammol ointmentcontaining respectively 50%. 20%, and 5% of ichthammol. In whatproportion should they be mixed to prepare a 10% ichthammol ointment? 50% 20% 5% 10% 5 5 40 + 10 = 50 50% : 20%: 5% 5 : 5 : 50

in what proportion may a pharmacist mix 20%, 15% ,5% , 3% zinc oxide ointment to produce 10% ointment 20% 15% 5% 3% 10% 5 20% 15% 5% 3% 10% 7 7 5 OR 10 5 5 10

Liquid Paraffin emulsion Rx Liquid Paraffin ℥ss 15 ml Gum Acacia Q.S. Spirit Mentha min xv (15 x 0.06 = 0.9 ml) Water to ℥ii 60 ml Fiat: Haustus Sig.: Statin Keep in a cool Place Shake The Bottle The Draught To be taken at once.

Liquid Paraffin is a mineral oil Prepared using the dry gum method Uses It softens fecal contents by retarding water reabsorption, so it is useful in chronic constipation. O W G 3 2 1 15 ml 10 ml 5 g

10 ml Water on the otherside Trituration must be: From the wrist. In one direction. In all parts of the morter. Continueous. Very Fast. 10 ml Water on the otherside 15 ml Oil on oneside In a dry mortar; add gum & grind with pestle Place gum in a line in the center Triturate with whipping motion until primary emulsion is formed (white , thick ,cracking sound) Continue triturating for 2 min. (stabilization)

Add to emulsion portionwise with stirring In test tube put 10 ml water + 0.9 ml spirit mentha Mix well Add to emulsion portionwise with stirring 10ml Water portion-wise & triturate 10ml Water Dpwise & triturate Wip with a tissue Adjust volume to 60 ml Transfer to a cup measure Primary Emulsion

Turpentine oil emulsion Rx Turpentine oil 8 ml Gum Acacia Q.S. Water to 40 ml Fiat: Haustus Sig.: Statin Keep in a Cool Place Shake The Bottle The Draught To be taken at once.

Turpentine oil is a volatile oil Prepared using the dry gum method and wet gum method (prepared twice) O W G 2 1 8 ml 8ml 4 gm

8 ml Water on the otherside Trituration must be: From the wrist. In one direction. In all parts of the morter. Continueous. Very Fast. 8 ml Water on the otherside 8 ml Oil on oneside In a dry mortar; add gum & grind with pestle Place gum in a line in the center Triturate with whipping motion until primary emulsion is formed (white , thick ,cracking sound) Continue triturating for 2 min. (stabilization)

Transfer to a cup measure 10ml Water portion-wise & triturate 10ml Water Dpwise & triturate Wip with a tissue Adjust volume to 40 ml Transfer to a cup measure Primary Emulsion