Solution Dosage Forms

Question 1

Drugs in solution dosage forms

Answer 1

Solute. Small molecular or larger peptides and proteins

Question 2

Solvents in solution dosage forms

Answer 2

Excipient that solute dissolves in. Polarity and toxicity are important considerations. Cosolvents may be necessary

Question 3

Use of excipients in solutions

Answer 3

Increase solubility, pH buffering, maintains stability (physical, chemical and microbiological), better absorption, colouring and flavour enhancement

Question 4

What patients have an insufficient swallow reflex for tablets

Answer 4

Children under 12 (undeveloped) and older persons (muscle atrophy)

Question 5

Solutions advantages over tablets

Answer 5

Easier swallowing, rapid absorption (doesn’t need to be liberated), flexible dose adjustment (homogenous solution = uniform drug conc in solution), no need to shake dosage form (better then suspension) and lower chance of GI irritation

Question 6

How tablets cause GI irritation

Answer 6

Tablets in stomach are concentrated at 1 point on wall. Large concentration of drug enters and gets trapped into samll group of gastric cells, killing them

Question 7

Solution Disadvantages

Answer 7

Bulky (hard to transport and store), more frequent dosing (due to rate of absorption), more susceptible to chemical degradation and microbe contamination, poor taste

Question 8

What makes solutions more sensitive to chemical degradation

Answer 8

Drugs in water can be subject to neutrophilic/electrophilic attack by water and degradation due to oxidation in water

Question 9

Aromatic Oil Outline

Answer 9

Oil (hydrophobic) is shaken in water. A tiny (negligible) fragment of oil dissolves in water (no cosolvent). Don’t tend to have therapeutic effects (exception peppermint and flatulence).

Question 10

Concentrated Water Outline

Answer 10

Higher concentration of oil in water (due to cosolvent) then in aromatic waters

Question 11

Concentrated Oil Outline

Answer 11

Higher oil content then water

Question 12

Spirit Outline

Answer 12

Solution where an alcohol is the main solvent (sometimes with water) and a volite substance

Question 13

Elixir Def

Answer 13

Oral solutions with alcohol as a cosolvent. Unsuitable for children as they don’t have alcohol metabolism (results in hyperglycemia). Alcohol doubles as a perservative. Eg paracetamol

Question 14

Syrup Outline

Answer 14

Oral aqueous solution contains high concentrations of sucrose or other sugars (more sugary if plant based). Sugar acts as a preservative (bacteriostatic). Acts as a demulcent (coating on throat prevents gas irritation)

Question 15

How syrups are susceptible to bacterial infections

Answer 15

Due to an intense heat change over a short amount of time. Condensation builds in bottles forming a layer of water (low in sugar on top). This layer can be easily infected

Question 16

Invert Syrup Outline

Answer 16

Breaks down sucrose into fructose and glucose. Different polarity and sweetness then other syrup

Question 17

Syrup Disadvantages

Answer 17

Sugar conc impacts other excipient solubility, susceptible to surface dilution, tooth decay and not accessible for diabetics

Question 18

Cap locking Outline

Answer 18

Screw on caps for syrups. When syrup spills on lid, it recrystalises making it hard to turn cap. Sorbitol, glycerol and other polyhdric alcohols can be excipients in syrups to reduce recrystalisation in syrups not For children

Question 19

Expectorate Outline

Answer 19

Coughing stimulant

Question 20

Linctus Outline

Answer 20

Viscous oral liquid. Due to it’s slow movement it properly coats the throat (demulcent)

Question 21

Mixture Def

Answer 21

Solution/suspensions with 2 or more active ingredients dissolved, suspended or dispersed in a suitable vehicle

Question 22

Mouthwashes Outline

Answer 22

Dosage form used to cleanse oral cavity. Don’t swallow

Question 23

Gargles Outline

Answer 23

Aqueous solution containing antiseptics, antibiotics and anesthetics. Used to treat the pharynx, by forcing air from lungs

Question 24

Oral Drops Outline

Answer 24

Oral solutions/suspensions administered with small volume with a metered device

Question 25

Oral Solution Outline

Answer 25

Local and systemic effects. Administered in 5ml doses (spoon, syringe and cup). Contained in amber bottles (prevent catalytic oxidation due to light) with child proof locks. Greater viscosity then water. Average pH is 7 (range 2-9)

Question 26

Parenteral Outline

Answer 26

Sterile, pyrogen free. pH to be similar to site of admin to prevent precipitation (phlebitis). Perservatives are used in a multidose. Aqueous and isotonic