Calculations & Compounding

weight (lbs)/height (in^2) x 704.5

/= 30 obese

Agar, carrageenan and gelatin

- Tween is a surfactant - Surfactants are compounds with polar sides and nonpolar sides - Surfactants are used as wetting agents. Tween (or polysorbate, used as Tween 20, 60 or 80) is a commonly used hydrophilic (water-loving), non-ionic (the head is not charged) surfactant. Tweens are usually used for oil in water emulsions. Surfactants decrease the surface tension of a liquid or between a liquid and a solid. They are used as detergents, wetting agents, emulsifiers and dispersants. Surfactants have polar and non-polar sides.

The amount of surfactant required is determined by the hydrophilic-lipophilic balance (HLB) number, which determines the relative degree of lipophilic and hydrophilic parts of the compound and (therefore) how much surfactant will be required to form the mixture together.

A two-phase system of two immiscible liquids, one of which is dispersed through the other as small droplets.

- Generally large stainless steel spatula blades are used, except plastic spatulas are used for chemicals (e.g. iodine) that can react with stainless steel blades - Glassine weighing paper (as opposed to Bond paper) should be used for weighing ointments and some dry chemicals. It is the safest not to use ointment paper to prepare creams and lotions (use a slab and spatula instead)

Amino acids contain 4 kcal/gram; dextrose contains 3.4 kcal/gram.

Lotions, creams and ointments are all OIL IN WATER preparations. Lotions have the most water, followed by creams (which are therefore thicker), followed by ointments (the most oil of the three)

A solution is a liquid preparation of soluble chemicals dissolved in solvents such as water, alcohol, or propylene glycol

The calcium and phosphate in a PN should not exceed 45 mEq/L. An excess can precipitate and lead to a pulmonary embolus.

Multivitamins, trace elements, electrolytes and insulin are all items that may be added to a patient's PN

- Severe gut dysfunction due to various conditions, such as Crohn's disease, ulcerative colitis, obstruction and short bowel syndrome from surgery - Patients requiring long-term supplemental nutrition because they are unable to receive daily requirements through oral or enteral feedings - NOT patients who are NPO due to surgery

Sweetener (sugar substitute) Thickening agent in liquids Plasticizer for gelatin capsules Sorbitol can cause GI distress, including cramping. It may be particularly bothersome to patients with IBS. Sorbitol used to be given in a formulation of sodium polystyrene sulfonate (Kayexalate) for the treatment of hyperkalemia, but the use of Kayexalate with sorbitol can result in GI (colonic) necrosis and is not recommended.

- FDA-approved and regulated drugs must have an approved NDA - They must be produced under Good Manufacturing Practices (GMPs) - They must have an expiration date that is provided to the pharmacy - They must each have an NDC number

0.6-1.2

- Surfactants, such as tweens and spans, can be used when preparing emulsions - Common examples of emulsions include propofol and mayonnaise - An emulsion is two or more liquids which are not able to be blended together (they are immiscible) - Emulsions can be given IV An emulsion is a mixture of two or more liquids which are immiscible (the two substances do not form a suspension-which means they stay separate when you combine them). Oil-in-water emulsions are used for oral formulations; patients could not tolerate an emulsion that was water-in-oil due to poor taste. However, oil-in-water (o/w) (or water-in-oil, or w/o) emulsions are suitable for topicals (drugs applied to the skin). Surfactants (with their hydrophilic and lipophilic ends) exist at the interface between the oil and water phases to keep the preparation together. In addition to o/w and w/o emulsions can also be water-in-oil-in-water (w/o/w). Emulsions are always liquid in liquid-the terms does not refer to solids in liquids, which are generally solutions or suspensions.

[WBC x (% segs + %bands)]/100

1 mEq = mmols x valence

BEE x activity factor x stress factor

3785 mL

21.1%

40%

Anion gap = [Na+] - [Cl-] - [HCO3-] normal range: 8-16 mEq/L

SR/% of error

454g

mOsmol/L = [wt of subtance (g/L)/MW (g/mole)] x (# of particles) x 1000

(58.5)(i)/(MW)(1.8)