Dosage Forms Flashcards

0
Q

What is the aim of dosage form design?

A

To achieve a predictable therapeutic response to a drug included in a formulation which is capable of a large scale manufacture with reproducible product quality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Am what are the eight functions of additives?

A
Solubilise 
Suspend
Thicken
Preserve
Emulsify
Modify dissolution 
Improve the compressibility 
Improve the flavor of drug substances
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the requirement for product quality?

A
Chemical and physical stability
Preservation against microbial contamination 
Uniformity of dose of drug
Acceptability to users 
Suitable packaging and labelling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Give examples of oral dosage forms (DF)

A

Solutions, tablets, capsules , powders ect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Give an example of rectal DF

A

Ointments, crams , powders ect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Give examples of topical DF?

A

Ointments, creams , lotions, gels, solutions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Give examples of parenteral DF

A

Injections , implants ect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give examples of respiratory DF?

A

Aerosols , sprays , inhalations ect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Give an example of nasal DF

A

Solutions, inhalations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give an example of eye DF

A

Solutions , ointments , creams

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Give examples of ear DF

A

Solutions, creams , ointments and suspensions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are three factors to be considered before the formulation of a dosage form?

A

Factors affecting drug absorption from different administration routes
Drug factors such as solubility
Clinical indication and Patient factors such as age , body weight other illnesses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What issues are important to design dosage forms?

A

Drug absorption
Drug distribution
Metabolism
Excretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What form must a drug be in to be absorbed via the membranes and epithelial of the skin, gastrointestinal tract and lungs into the body fluids?

A

Drug must be in solution form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the rate of diffusion influenced by?

A

Lipid solubility and ionisation degree of the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Give an example of a specialised transport mechanism

A

Glucose transport to the brain via the glucose receptor located on the blood brain barrier
Or
P-go protein which is an ATP-dependent efflux pump capable of transporting many drugs across cell membranes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is first pass metabolism?

A

Where the concentration of s drug is greatly reduced before it reaches the systemic circulation. It is the fraction of lost drug during the process of absorption which is generally related to the liver and gut wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where does a drug enter once it is swallowed?

A

Absorbed by the digestive system and enters the hepatic portal system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where is the drug carried after the hepatic portal system?

A

Through the portal vein into the liver before it reaches the rest of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does the liver do in regard to drug metabolism?

A

It metabolizes many drugs sometimes to the extent that only a small amount of the active drug emerges from the liver to the rest of the circulatory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the problem of first pass metabolism?

A

It greatly reduces the bioavailability of the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the bioavailable fraction determined by?

A

The fraction of drug that is absorbed from the GI tract and the fraction that escapes metabolism during its first pass through the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How may the first-pass effect be avoided?

A

By considering other administration for example, intravenous, intramuscular, or sublingual that avoid the first-pass effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What must be adjusted if a different administration route is used?

A

The dosage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is needed if the metabolite is inactive?

A

A larger oral dose is required to attain the desired therapeutic effect than with a lower dosage in a route with no first-pass effect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Give an example of a drug with a high first pass metabolism

A

propranolol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is needed if the metabolite is active?

A

Oral dosage must be carefully tailored to the desired therapeutic effect. First-pass metabolism in this case will result in a quicker therapeutic response than that achieved by a rout with no first-pass effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the fastest to slowest in terms of onset of action?

  1. intra muscular injections
  2. buccal tablets
  3. capsules
  4. intra venous injections
  5. depot injections
A

4>1~3>2>5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How long to intra venous injections take till onset of action?

A

seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How long does intra muscular, buccal tablets, aerosols and gases take till onset of action?

A

minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How long do short- term depot injections, capsules ect. Take till onset of action?

A

Minutes to hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How long do enteric-coated formulation take till onset of action?

A

Several hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How long do depot-injection and implants take till onset of action?

A

Depot injections, implants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are the routes of drug administration?

A
Oral/buccal/sublingual
Respiratory route
Nasal
Topical route
Ocular
parenteral route
Rectal route
vaginal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What route of drug administration is the safest?

A

Oral route

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is absorbed by in the oral route?

A

Mucosa and various epithelia of GI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the problem with the oral route?

A

Slow onset of action
Risk of irregular absorption
Destruction of drugs by enzymes and secretions of the GI tract (e.g. insulin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Where are weak acids better absorbed?

A

Stomach pH 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Where are weak bases better absorbed?

A

In the intestine 7-8pH of the large intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are the most popular oral dosage forms?

A
Tablets
Capsules
Suspensions
Solutions
Emulsions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is sublingual route?

A

When dosage is put under the tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is buccal route?

A

In the pouch of the cheek

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Why is sublingual mucosa more permeable to the buccal mucosa?

A

Due to higher vascularisation and thinner epithelium (rapid onset of action)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What are problems of sublingual route?

A

Cannot be used for systemic transmucosal drug administration due to the wash of the area by saliva, thus there is little time for the drug to be retained at the site of action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Give an example of sublingual administrated drug?

A

nitriglycerin for patients with heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are general advantages of oral route of drug administration?

A

Non- invasive , well-accepted ,convient ,accessible
First-pass metabolism by the liver is avoided
Drugs can be given to unconscious patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are the advantages of sublingual routes?

A

Fast onset if drug action due to higher permeability

Local action of drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What are advantages of buccal routes?

A

Local and systemic effects (oral transmucosal delivery)
Suitable for proteins and peptides due to immobile mucosa and extended smooth muscle area so longer retention to the region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What are disadvantages of buccal route?

A

Low drug bioavailability due to low flux of the drug through the buccal mucosa due to low permeability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Why are anti-nausea medicines used via the buccal route? the dosage forms of respiratory

A

The nausea itself can cause swallowed tablets to be vomited and therefore rendered ineffective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What dosage forms are used for sublingual and buccal use?

A

Tablets

Soft gelatine capsules filled with liquid drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What are the dosage forms of respiratory route?

A

aerosol, gas, inhalation to the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is the aim of the respiratory route?

A

For treatment od airways diseases (bronchial asthma, cystic fibrosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What do lungs provide?

A

A large surface area for drug absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Is first pass metabolism avoided using respiratory route?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is aerosol?

A

A two-phase system of solid particles/liquid droplets dispersed in air/other gaseous phase, having small size to enable stability as a suspension.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is the deposition of a drug/aerosol in the airway dependent on?

A

Physicochemical properties of the drug
The formulation
The delivery/liberating device
The patient (breathing pattern and clinical status)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What are the particle size that reaches the peripheral regions (bronchioles and alveolar regions)?

A

5 or 6 micrometres

58
Q

What is the particle sizes that reach the alveolar sacs?

A

0.5-1 micrometers

59
Q

What can happen to large particles or droplets deposited on the upper respiratory tract ?

A

They can be cleared from the lung by the mucocilliary action, so the drug becomes available for systemic absorption and causes side-effects

60
Q

What is a nebulizer?

A

When the drug solution/suspension is contained in the nebulised is converted to a fine mist which is inhaled through a mouthpiece or face-mask

61
Q

What is a metered dose inhaler?

A

Pressurized canisters fitted with a metering valve. A predetermined dose is released as a spray every time that the metring value is activated.

62
Q

What are advantages of nasal drug delivery?

A

Large surface area (160 cm squared) and a rich blood supply
Avoids first-pass metabolism
Absorption levels reach some levels similar to those as if the drug was administrated intra-venous.

63
Q

What are the disadvantages of the nasal drug delivery?

A

Metabolism and degradation of drug due to high enzymatic action of the nasal mucosa. Although esterases can be useful for prodrugs
Mucous flow and biliary movement will remove some of the drug towards the orifice of the noise which lead to drug lost
Swallowing can lead to systemic effect

64
Q

What is topical-transdermal route?

A

Application of the drug onto the skin with aim to treat, protect, restore locally (more common) or to achieve systemic administration via delivery across the skin (transdermal) for conditions such as angina, pain, motion sickness

65
Q

What are dosage forms of topical-transdermal route?

A

Cream, ointment, gels
Location, solution, aerosols
Transdermal patches

66
Q

What is drug penetration via the transdermal route controlled by?

A

Stratum corneum hydration (this Si the outermost layer of the epidermis, consisting of dead cells that lack nulcei and organelles)
Temperature
pH
Drug concentration
Molecular characteristics of the drug
The vehicle that the drug is solubilised/dispersed in

67
Q

What are advantages of transdermal route?

A

First-pass metabolism is avoided
Irritation to the GI tract is eliminated
Non- invasive and can be self-administrated
Can provide release for long period of time
Inexpensive

68
Q

What are disadvantages of transdermal route?

A

Limited number of drugs are amenable to administration by this route
Only small molecules quite hydrophilic can pass freely across the skin without taking into account passing through stratum corneum (drug partition coefficient is very important)
Excess drug cannot be removed from the blood circulation

69
Q

What is the ocular route?

A

Drugs are administrated for local effects (mydriasis,miosis), anaesthesia or to reduce intraocular pressure

70
Q

Where is the drug delivered via the ocular route?

A

On the eye, into the eye or onto the conjunctiva

71
Q

What fraction of drug dose penetrates the eye?

A

1/10

72
Q

What does the conjunctiva?

A

Helps lubricate the eye by producing mucus and tears, although a smaller volume of tears than lacrimal gland
It also helps prevent the entrance if microbes into the eye

73
Q

What is the cornea?

A

Is the transparent front of the eye that covers the iris, pupil, and anterior chamber.

74
Q

What is the pre-corneal tear film?

A

A thin layer of lubricating substance

75
Q

What is the pH of the eye?

A

7-7.4

76
Q

What are factors affecting drug permeation?

A

Ionization and pH
protein binding
Drug distribution in the eye:
Rate of drug loss from the precorneal area
Rate of drug uptake by cones
Drug penetration through the sclera (white of the eye):
Through perivascular spaces
Through the aqueous media of gel-like mucopolysaccharides
Across the scleral collagen fibrils

77
Q

What are factors influencing drug retention?

A

Proper placement of eye drops
Influence of instilled volume
Preservatives
Effect of systemically admistrated drugs

78
Q

What do topically applied timolol and antihistamines do?

A

Reduce tear flow

79
Q

What drug stimulates tear flow?

A

Topically applied pilocarpine

80
Q

What do general anaesthetics inhibit?

A

Lid movement

81
Q

What are dosage forms for ocular delivery?

A

Aqueous solutions ad suspensions
Ointments (longer drug contact with the eye)
Inserts (oculosert: pilocarpine)

82
Q

What are requirements of drugs for ocular delivery?

A
Sterility
Free of any small particles
PH 7.4
Toncity
Viscosity
83
Q

What are the three main parenteral routes?

A

Intravenous
Intramuscular
Subcutaneous

84
Q

What is the parenteral route?

A

A drug is injected via a hollow needle into the body at various sites and depth

85
Q

What are some less frequently used parenteral routes of administration?

A

intraarteial
intraperitineal
intracardiac
intrathecal

86
Q

What is intravenous injection?

A

Provides the most rapid drug onset of action-no barrier to absorption
e.g. chemotherapeutic agents

87
Q

What is intramuscular?

A

Less hazardous, easier to use but more painful and with longer onset of drug action then the i.v. injection

88
Q

What is the difference between i.v. and i.m injections?

A

Drugs levels in the blood of i.mare lower to those achieved with i.v because the drug has to be absorbed by the tissue. The absorption is depended on various factors such as depth of injection, muscle exercise, local blood flow supply, ect.

89
Q

How can depot be formulated?

A

Suspension of the drug in aqueous or oily vehicles, emulsions

90
Q

What is the order of onset of action of injections?

A

s.c slower than i.m (due to lower blood supply ),slower than i.v

91
Q

Give example of sc. drugs?

A

Heparin and insulin

92
Q

When/why would you take parenteral route?

A

Rapid absorption is essential
Emergency situations or patient is unable to take oral medication
Drug is either destroyed, or inactivated or poorly absorbed in case of oral administration

93
Q

What are advantages of parenteral route?

A

Fast drug absorption and drug action

Blood levels are more predictable than those achieved by oral dosage forms

94
Q

What are disadvantages of parenteral route?

A

Expensive
Must be sterile
Trained personnel is required
Difficulty with removing the drug from circulation in case of adverse effect or overdose

95
Q

When is rectal route used?

A

When drugs are inactivated in GI tract
Patient unable to take oral medication due to unconscious, vomiting, postoperative
Drugs are used for local action

96
Q

What are dosage forms for the rectal route?

A

Cleansing solutions
semisolids preparation
Solid preparations

97
Q

What are the 3 heamorrohodial veins that supply the rectum?

A

Middle and lower vein that drain directly into the general circulation , upper one drains into portal vein leading to the liver

98
Q

What are the disadvantages of the rectal route?

A

Drug metabolism in the liver do the bioavailability will be less than 100%
Irregular and unpredictable drug absorption depended on the part of the rectum the drug is absorbed

99
Q

What are advantages of vaginal route?

A

Higher bioavailability than oral route

First-pass metabolism in liver avoided

100
Q

What are disadvantages of vaginal route?

A

The thickness of the vaginal epithelium and blood circulation of this region changes with menstrual cycle and age, thus drug absorption is altered

101
Q

What are dosage forms for vaginal administration?

A

Tablets, capsules, solutions, creams ect.

102
Q

Name the types of dosage forms?

A

Liquid
Semi-solid
Solid

103
Q

Give examples of liquid dosage forms?

A

Aerosols, ear and eye drops,lotions ect.

104
Q

Give examples of semi-solid?

A

Creams, gels,ointments

105
Q

Give examples solids?

A

Capsules, powders,pasteilles

106
Q

What are solutions of liquid dosage forms?

A

Homogenous mixtures of two or more salutes dissolved in one or more solvents

107
Q

Name some oral solutions

A

Syrups-aqueous solutions that contain sugar
Elixirs- clear flavoured liquids contain a high proportion of sucrose or a suitable polyhydric alcohol and sometimes alcohol
linctuses- viscous liquids used in the treatment of cough
Mixtures- oral and suspensions
Oral drops
Mouthwashes
gargles

108
Q

What is the isotonic and pH of nasal solutions?

A

0.9% & pH 5.5-6.5

109
Q

What does overuse of topical decongestants result in?

A

Oedema of nasal muscosa

110
Q

What are enemas?

A

Oily or aqueous solutions administrated rectally used to treat constipation or ulcerative colitis or X-ray examination of the lower bowl

111
Q

What are suspensions?

A

Liquid dosage forms where the active ingredient/s are isoluble in an aqueous or oily vehicle

112
Q

What are emulsions?

A

Mixtures of two immiscible liquids, usually oil and water to form small droplets

113
Q

What are applications?

A

Solutions, suspensions or emulsions used for topical use.

114
Q

What are lotions?

A

Solutions ,suspensions or emulsions door external use

115
Q

What are liniments?

A

Liquids for external uses to alleviate the discomfort of muscle strains and injuries

116
Q

What are collodions?

A

Liquids for external use used to seal minor cuts and wounds that have partially healed.

117
Q

What are aerosols?

A

Drug in solution/suspension in pressurized pack in presence of suitable propellant. Used for asthma or topically for muscle sprains and injuries

118
Q

What are inhalation?

A

Volatile substances for use on the upper respiratory tract disorders like nasal congestion

119
Q

What are irrigation?

A

Sterile solutions used for treatment off infected bladders

120
Q

What are paints?

A

Solutions for application to the skin or mucous membrane. For skin paints are formulated with a volatile vehicle. When used for the throat and mucous surfaces a viscous vehicle is included normally, so to retain the preparation on the infected area

121
Q

What are eye drops?

A

Sterile preparations used to administer drugs to the eye

122
Q

What are injections?

A

Sterile, progeny-free preparations for parenteral administration

123
Q

What are pyrogens?

A

Fever producing organic substances due to microbial contamination

124
Q

What vehicles are used for injections?

A

Aqueous- sterile water for injection, bacteriostatic

nonaqueous- fixed vegetable oils, glycerine, alcohols

125
Q

What are oleaginous injections mostly used?

A

Intra muscular

126
Q

What are some semi-solid dosage forms?

A

Gels
Creams
Ointments
Pastes

127
Q

What are gels?

A

Transparent or translucent dosage forms for local use, for eczema, psoriasis ect.

128
Q

What are creams used for?

A

Emulsions for external use. Microbial contamination is possible due to the water consent so preservatives are added or short shelf life

129
Q

What are ointments?

A

Oily semisolids for topical use as emollient or drug delivery to the surface or for deeper penetration into the skin

130
Q

What are pastes?

A

Vehicles with high concentration of solid material (like starch)

131
Q

Name solid dosage forms?

A
Tablets
Capsules
Dusting powders
Powders(oral)
Granules
Lozenges
Pastilles
Implants
insufflations
Suppositories
Pessaries
Transdermal delivery systems
132
Q

What are tablets?

A

Prepared by compression and contain drugs and excipients for specific functions

133
Q

What are capsules?

A

Drugs and appropriate fillers are enclosed in a hard or soft gelatin shell, content can be liquid or powder or small pellets with different coatings

134
Q

What are dusting powders?

A

Finely divided powders for external use. Used as disinfection and antisepsis in minor wounds lubricants to prevent friction between skin surfaces

135
Q

What are powders (oral)?

A

They can be packed as bulk e.g. antacids or divided powders e.g. sachet

136
Q

What are granules?

A

Small particles of irregular shape

137
Q

What are lozenges?

A

Large tablets designed to be sucked and remain in the mouth for 15 min. For mouth and throat infections

138
Q

What are pastilles?

A

Used as lozenges. They contain antiseptic as active substances and are jelly like and basic component is acacia or gelatin. used to treat mouth and throat infections

139
Q

What are implants?

A

Placed under the skin by a small surgical incision. They are used as hormone replacement therapy or contraceptive. They are long term therapy due to slow drug release (3yrs). They must be sterile.

140
Q

What are insufflations?

A

Drugs in dry powder form in a capsule. Administration involves a device where the capsule is broken and the powder is inhaled by the patient. It is used to treat asthma.

141
Q

What are suppositories?

A

Are inserted into the rectum for local or systemic action

142
Q

What are pessaries?

A

Are inserted into the vagina for both, local and systemic action

143
Q

What are transdermal delivery systems?

A

Adhesive patches, which release the drug in a controlled manner for a specified time to produce a systemic affect.