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Flashcards in Parenterals Route Deck (28)
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1

Parenteral route is...

drug administration by injection

2

Advantages of parenteral: (3)

works for unconscious patients

intravenous route means rapid onset of action

avoids first pass metabolism, thus improves bioavailability

3

Disadvantages of parenteral: (3)

need a healthcare professional

needle stick injuries, needle phobia

shelf life shorter, expensive to store

4

Intravenous route..

via a surface vein, 100% drug absorption

5

Infusion provides..

a slow and controlled drug release rate

6

What can't be administered via IV? (2)

water in oil emulsions - can block blood vessels

hypertonic / extreme pH drug solutions - cause inflammation and pain

7

Intra-arterial route..

via an artery

more invasive, less accessible
only used when IV access cannot be established e.g. pre-mature babies

8

Intra-cardiac route...

used only in life-threatening emergencies to produce a rapid, local effect in the heart

9

Intra-dermal injections..

into the skin between the epidermis and dermis

slow absorption (little interstitial fluid to faciliate drug diffusion)
used for immunological diagnostic tests and vaccinations

10

Subcutaneous injections / hypodermic...

into the loose connective and adipose tissues immediately below the dermal skin layer e.g. abdomen /upper arms and legs

highly vascular site so rapid absorption

11

Intramuscular injections..

into the tissue of a relaxed muscle in buttock, thigh and shoulder

absorption is slower than subcutaneous

12

Intrathecal injection...

into the cerebrospinal fluid CSF in the subarchnoid space of spinal canal

allows drugs to bypass the blood brain barrier

100% drug absorption

13

Epidural injection..

in the epidural space between the dura mater and the vertebrae

14

Intra-articular injections...

into the synovial fluids of joints cavities

100% absorption

15

Intraocular...

into the eye

intacameral injections - in anterior chamber

intravitreal - in the vitreous chamber

16

All parenteral preparations must be...

sterile

as the drug bypasses the body's natural defence mechanisms

17

Excipients may be added to...

adjust pH
increase solubility / stability / shelf life
preservatives

18

What are Endotoxins and Pyrogens?

What is the significance?

Endotoxins - lipopolysaccharides found in the outer membrane of Gram-negative bacteria.

Pyrogens - substances that cause fever, typically produced by bacteria or viruses.

Parenteral preparations must be free from these

19

Significance of particulates?

suspensions must be free of visible and sub-visible particles - or else they will travel through the venous system to the lung, preventing blood flow

20

Containers must be..

transparent
glass/plastic
effectively sealed
be airtight

21

Sterile productions can be in..

solutions
clear and free from particles

suspensions
suspended by shaking


emulsions
no signs of creaming or cracking

22

Aqueous injections for multiple dosing must contain...

an antimicrobial preservative unless its self-preserving

23

What are infusions like?

sterile aqueous solutions or emulsions

continuous phase is water

isotonic formulation with respect to blood

100ml - 1000ml

24

How are concentrates administered?

through infusion bags

diluted with saline or water for injection

25

How are powders administered?

required volume of diluent is added prior to administration

used for drugs with short shelf life after dissolved in solution

26

How are suspensions administered?

must first be dissolved before absorption takes place - allows slow and prolonged release thus can reduce dosing frequency.

27

What else may be added?

co-solvents e.g. ethanol

solubilising agents

antioxidants, extend product shelf life / nitrogen gas bubbled through

preservatives

ph adjusters and buffers

tonicity adjusting agents

suspending agents in suspensions

28

When are glass containers used?

for single use unpreserved products

type 1 glass used as there is little interaction with formulations.

but they are fragile and carry safety risk