2. What mean Routes of Drug Administration?
-The path by which a Drug, fluid, poison, or
other substance is come into contact with the body .
- May be systemic topical .
The possible routes of drug entry into the
body may be divided into classes :
*Enteral.
*Parenteral.
*Inhalation (Pulmonary absorption).
*Topical Application.
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4. Drug placed directly in the GI tract, desired effect is
systemic (non-local), substance is given via
the digestive tract
-oral
-sublingual
-buccal
-rectum Absorption through the rectum
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6. Advantages
1-Convenient
can be self administered, pain free, easy to
take, more safe and acceptable to patient.
2-Cheap
compared to most other parenteral routes.
3-Systemic distribution
Disadvantages
1-Absorption variable
absorption slow or irregular
2-First-pass effect
drugs absorbed orally are
initially transported to the liver via the
زportal vein
3-Esophageal ulceration
-irritation to gastric mucosa
nausea and vomiting.
4-Destruction of drugs by
gastric acid and digestive
juices .
insulin, oxytocin destroyed in gutDr .safia A alrezami
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7. Dis advantage : unpleasant taste and Only for lipid soluble drug.
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8. the area inside the mouth between the lining of cheek (the buccal mucosa ) and the
teeth / gums . Certain medications are designed to be given bucally .
Buccal (as opposed to oral) administration usually results in a more rapid onset of
action, since the medication need not pass through the digestive system and can be
absorbed directly through the skin. There is current research on developing buccal
morphine, as well as insluine . Some sedatives can be given buccally, e.g. midazolam .
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9. Absorption through rectum
various drugs in suppository or enema form
Like sublingual not effect by first pass metabolism
or enzyme
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10. Advantages
1-Unconscious patients
and children, if patient is
nauseous or vomiting .
2. The metabolism of drugs
by liver is minimized.
3.Good for drugs affecting
the bowel such as laxative.
Disadvantages
1-Absorption incomplete
irregular in lower rectum.
2. Irritation.
3- Un–accept route by patient .
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11. Need in
1-poorly absorbed drug from GIT e.g insulin
2-Unconscious patients
3-Rapid onset of action
4-Control over the actual dose of drug
:( ampule ,vials).
Three major parenteral :
Intravascular (IV)
placing a drug directly into the blood stream.
Intramuscular(IM)
drug injected into skeletal muscle.
Subcutaneous(SC)
Absorption of drugs from the subcutaneous tissues.
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12. Advantages
1- Direct to the blood.
2-If drug un stable in GIT.
3- NO first pass metabolism.
4-For un conscious patient .
Disadvantages
1- Need sterility .
2- Need experience.
3-Painful.
4- Can not adverse the effect
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13. Use
•Suitable for large
volume, irritating drugs.
• Must inject slowly as a rule.
• Complete bioavailability.
• E.g Thiopentol, diazepam IV
for quick effect
Advantages
• Direct.
• No first pass effect .
• IV inj. Immediate effects.
• Valuable for emergency.
Disadvantages
• Requires IV access.
• Hard to remove.
• Vascular injury.
• Lack of sterility may cause
viral hepatitis or AIDS.
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14. Use
•Suitable for small volume of
oil drugs.
• Must inject slowly.
Advantages
• Good for depot storage
(if oil based) Rapid onset of
Action.
e.g vaccines, antibiotics.
Disadvantages
• Pain at site of injection
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15. Use
•Suitable for large
volume, irritating drugs.
• Must inject slowly as a rule.
• Complete bioavailability.
• E.g Thiopentol, diazepam IV
for quick effect
Advantages
• Non irritating small volumes Even
slow absorption
e,.g Adrenaline in local anesthetics
.
Disadvantages
• Pain, necrosis,
• Absorption of solid pallets
implanted under the skin occurs
slowly over weeks or months,
e.g Testosterone Insulin, adrenaline,
heparin, vaccines inj.
SC.
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16. Immediate action in lungs Rapid delivery to blood
Local or systemic action.
*gaseous and volatile agents and aerosols
rapid onset of action due to rapid access
to circulation :
a. large surface area .
b. thin membranes separates alveoli
from circulation .
c. high blood flow.
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17. Advantages
Instantaneous absorption
User can titrate (regulate the
amount of drug they
are receiving).
Avoids hepatic first-pass
loss.
Local application at the
desired site of action in
pulmonary disease.
Treatment of bronchial
asthma.
Disadvantage
Must be in gas, vapor
or aerosol form.
In exactly dose .
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18. Dr .safia A alrezami
• is a medication that is applied to body
surface such as the skin or Mucosal membranes to treat ailments via a
large range of classes including but not limited to
creams, foams, gels, lotions, and ointments.
•Mucosal membranes
• (eye drops, antiseptic, sunscreen, callous removal, nasal)
•Skin
a. Dermal - rubbing in of oil or ointment
(local action)
b. Transdermal - absorption of drug through
skin (systemic action)
i. stable blood levels .
ii. no first pass metabolism .
iii. drug must be potent or patch
becomes to large .
19. Advantage
Convenient Effects are
limited to area of
application Localized.
Limited systemic
absorption.
Disadvantage
Effects are limited to
area of application.
Irritation .
No exactly dose .
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20. Dr .safia A. alrezami
Eye drops Ear drops Nasal drops