4. Route of Administration ( ROA).pdfNursing

Notes for Nursing students pharmacology Route of Administration

1. Official (Closed) -Non Sensitive
Route of Administration (ROA) of
medications and Abbreviations
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2. Official (Closed) -Non Sensitive
Definition of ROA
A means or way a drug/ medicineor poison is brought into
contact with the body
The Choice of the ROA depends on:
The pharmacokinetics of the drug and the patients requirements
andcondition
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3. Official (Closed) -Non Sensitive
Different ROA to make the choice
Route of Administrations are of 3 big groups:
•Enteral
•Parenteral
•Topical
Into the system, any other way
besides GIT
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4. Official (Closed) -Non Sensitive
Enteral
Passing through the intestine, either naturally via the mouth and
esophagus, or through an artificial opening
Means - route of administration of the medication is via the GIT
Types:
•Oral-tablets and Liquid prep given orally,
•Buccal, S/L, (sublingual)
•PEG(percutaneous endoscopic gastrostomy) ,
•NG
•Per-Rectal-SUPPOSITORY
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5. Official (Closed) -Non Sensitive
Advantages of Enteral Route-Oral and
Sublingual
Oral
•Convenient-easy to take, no pain
•Cheap-no need to sterilize, kept in
seals
•Variety of choices fast-fast
release, enteric coated, SR,
suspensions, mixtures
Sublingual
•The liver is by- passed- No First
Pass effect
•Rapid absorption due to
blood supply
•Drug stability-pH in mouth
neutral
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6. Official (Closed) -Non Sensitive
First Pass Effect
First pass Effect
What is it ?
•The first pass effect is a phenomenon in which a
drug gets metabolized in the liver before it is
absorbed by the intestines. This results in a
reduced concentration of the active drug upon
reaching its site of action or the systemic
circulation.
•All oral drugs-undergo First Pass Effect.
•Therefore –the bioavailability of oral drugs is the
lowest.
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7. Official (Closed) -Non Sensitive
Disadvantages of Enteral Route-Oral and
Sublingual
Oral
•Drugs suffer poor bioavailability
•Undergo First-pass effect
•Food timing may interfere with medication
timing-food -drug interaction
•Antibiotics kill gut flora-leading to fungal
varieties
•Unconscious/ dysphagic/ pediatric pt cannot
swallow
Sublingual
•Holding in mouth is inconvenient
•Accidentally swallowed it may
affect MOA
•Only small doses
•Mucosal irritation
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8. Official (Closed) -Non Sensitive
Compare-SL vs Oral
SL
•Faster absorption into Systemic blood flow-rich with
vessels under tongue
•Higher bioavailability of meds as-
NOFIRST PASS EFFECT”
•As mouth PH more neutral than stomach-less
alteration to drug
Disadvantage
•Can cause mucosal irritation,
•difficult to hold larger tablets thus inconvenient for
older folks and younger children and
•if accidentally swallowed-becomes altered oral route
which may affect bioavailability. Also, may accidentally
e chewed.
ORAL
Easy to self administer and more
convenient
Usually, oral route of medications are
cheaper and affordable
Advise needs to be clear-SR and
Enteric coated not to chew
Disadvantage
Bioavailability reduced due
to “FIRST PASS EFFECT”
Strong Stomach acidity-may alter drug
and reduce drug bioavailabity
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9. Official (Closed) -Non Sensitive
PARENTRAL Route…….
The desired effect is through the
systemic path to the intended
target,
other than via oral route :
Entry could be through
•Vessels
•Skin
•Muscles,
•Bone
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10. Official (Closed) -Non Sensitive
Through Vessels
Through Vessels
•Intravenous injections
•intravenous infusions
•Intra-arterial injections
•Intra-arterial infusions
•Intraosseous infusions- into bone
Intraosseous infusions
intravenous infusions
Intra-arterial infusions
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11. Official (Closed) -Non Sensitive
Injections
Through Skin and Muscle
IM injections
Subcutaneous injections
Intradermal
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12. Official (Closed) -Non Sensitive
Parenteral cont.….
Drugs delivered into-Body cavities
•Intraperitoneal-into the peritoneal cavity
•Epidural-into the subarachnoid space
•Intrathecal-into the cerebrospinal fluid
•Intra-articular-into joint cavities
Intracardiac:
This is an injection given directly into the heart muscle
ex: adrenaline during resuscitation, advance life support.
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13. Official (Closed) -Non Sensitive
Advantages and Disadvantages
Of Parenteral Route
Advantages
•When oral route is contraindicated-
seizures, coma, dysphagia, very ill
•Means of delivery when pt is critical-life
and death situation and time is short
•Intravenous route-bioavailability 100 %
•Rapid absorption
Disadvantages
•Risk of introducing infection
•Contra indicated for pt with
bleeding tendencies
•Too Rapid absorption for IV, Intra-
arterial,
•Expensive
•Trained professional needed to
administer
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14. Official (Closed) -Non Sensitive
TOPICAL ROUTE
•Topical route is applying medication externally directly to the local
area for its action.
•Some topical medication do have systemic action too.
https://en.wikipedia.org/wiki/Topical_medication
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15. Official (Closed) -Non Sensitive
Topical Types
•Epicutaneous-applying on
skin
•Transdermal-diffusion
through skin
•Ocular-onto conjunctiva
•Otic-into ear canal
•Intra nasal-into nasal
passages
•Per-vaginal
Epicutaneous
Intra nasal
Otic
Transdermal
Per-vaginal
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16. Official (Closed) -Non Sensitive
Topical Route
Advantages
•Helpful if esp. when oral route difficult for pts
vomiting or dysphagic (cannot swallow)
•For patients who are unconscious
•Avoids First Pass effect
•Convenient to administer
•No need a trained professional
•Cheaper formulation
Disadvantages
•Erratic absorption
•Not well tolerated by some
•Uncomfortable due to its oily nature
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17. Official (Closed) -Non Sensitive
Intravenous Route-ADVANTAGES
Advantages
•Rapid –A quick response is possible
•Total dose –The whole dose is delivered to the blood
stream. Large doses can be given by extending the time of
infusion/ bioavailability is 100%
•Veins relatively insensitive to irritation by irritant drugs at
higher concentration in dosage forms (as compared to other
parenteral route)
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18. Official (Closed) -Non Sensitive
Intravenous Route-DISADVANTAGES
•Suitable vein –may be difficult to find a suitable
vein
•Maybe toxic –rapid response, monitoring for
toxicity (as compared to oral)
•Requires trained personnel
•Expensive –sterility, pyrogenic testing and larger
volume of solvent means greater cost for
preparation, transport and storage
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19. Official (Closed) -Non Sensitive
Nursing Considerations
3 main aspects to be careful:
•when u choose the medication-safe guidelines to prevent
medication error
•When u give the medication-preventing error in administration
•When u are finally discharging patient-patient education
READ TEXTBOOK ON THIS ( page 26) Nursing implications
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