Understand everything about Routes of drug administration

1. MEDUSA PHARMACOLOGY DEPARTMENT:
GUNNERS PHARMACOLOGY LAB 3 Explanations and Revisional Questions.
CREATED by: ANDREW KG NJAMBA
"REMEMBER TO BE PASSIONATE ALWAYS"

2. Effect of Route of Administration upon Drug Action
INTRODUCTION
* Drugs are chemical substances that are used for the diagnosis, prevention, or treatment of disease states.
* There are various ways in which a drug can be administered to patients. These ways are known as routes of administration.
* The common routes of administration of drugs are oral, subcutaneous, intravenous, intraperitoneal, intrathecal, rectal, nasal,
inhalation, and topical application.
* Each route has its advantages as well as disadvantages.
* The magnitude, speed, and even the character of the biological response following the administration of a given amount of a drug
is largely determined by the route by which it is given.
Effect of Route of Administration on Drug Action
* The route of administration can affect the drug action in the following ways:
* Onset of action:The onset of action is the time it takes for a drug to reach its therapeutic effect. Intravenous administration has
the fastest onset of action, followed by inhalation and subcutaneous administration. Oral administration has the slowest onset of
action.
* Bioavailability: Bioavailability is the proportion of a drug that is absorbed into the bloodstream and reaches its target site of
action. Oral drugs have a lower bioavailability than injectable drugs because they must first pass through the liver, where some of the
drug may be metabolized and excreted.
* Duration of action:The duration of action is the time it takes for a drug to be eliminated from the body. Intravenous drugs have a
shorter duration of action than oral drugs because they are rapidly eliminated from the bloodstream.
Experiment on the Effect of Route of Administration on Drug Action
Aim:Study the effect of administration on drug action
*Drugs: Sodium Thiopentone 10 mg/cm3
and Sodium Pentobarbitone 6 mg/cm3**

3. Procedure:
1. One half of the class will administer Sodium Pentobarbital in a dose of 45mg/kg; the other half will administer Sodium
Thiopentone in a dose of 80mg/kg.
2. Each group will obtain 6 mice.
3. Weigh the mice and record the weights.
4. Determine the volume of barbiturate to be given to each mouse.
5. Inject the barbiturate into mice as follows:
* Intraperitoneally - 2 mice
* Subcutaneously - 2 mice
* Orally - 2 mice (accomplished using a feeding needle)
6. For each mouse, record:
* Time of administration of the drug.
* Time when the mouse goes to sleep.
* Time when the mouse wakes up.
After getting the Results answer the question below:
Question:
What are your observations and inference with regard to drug actions of SODIUM PENTOBARTONE and SODIUM THIOPENTONE on
each of the 3 routes used?
*Observations and Inference:
(1) Sodium Pentobarbitone
Onset of action:
* Intraperitoneal: Fastest
* Subcutaneous: Intermediate
* Oral: Slowest
Bioavailability:
* Intraperitoneal and subcutaneous: Highest
* Oral: Lowest
Duration of action:

4. * Intraperitoneal and subcutaneous: Shortest
* Oral: Longest
(2)Sodium Thiopentone
Onset of action:
* Intraperitoneal and intravenous: Fastest
* Subcutaneous: Intermediate
* Oral: Slowest
Bioavailability:
* Intraperitoneal and intravenous: Highest
* Subcutaneous: Intermediate
* Oral: Lowest
Duration of action:
* Intraperitoneal and intravenous: Shortest
* Subcutaneous: Intermediate
* Oral: Longest
Inference:
The route of administration has a significant impact on the drug action of both sodium pentobarbitone and sodium thiopentone.
Intraperitoneal and intravenous administration resulted in the fastest onset of action and highest bioavailability, while oral
administration resulted in the slowest onset of action and lowest bioavailability. Sodium thiopentone had a faster onset of action and
shorter duration of action than sodium pentobarbitone, regardless of the route of administration.
Conclusion:
The route of administration should be carefully considered when selecting a drug and determining the appropriate dose. Drugs that
require a rapid onset of action, such as emergency medications, should be administered intravenously or intraperitoneally. Drugs that
require a sustained effect, such as pain relievers, should be administered orally or subcutaneously.
Multiple Choice Questions on the Effect of Route of Administration on Drug Action

5. General MCQs
1. Which of the following routes of drug administration has the fastest onset of action?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
2. Which of the following routes of drug administration has the highest bioavailability?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
3. Which of the following routes of drug administration is most commonly used for emergency medications?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
4. Which of the following factors can affect the route of drug administration?
A. Patient age
B. Patient weight
C. Patient medical history
D. All of the above
5. Which of the following drugs is typically administered orally?
A. Insulin
B. Epinephrine
C. Morphine
D. Acetaminophen
Clinical Correlation
6. A 65-year-old man with a history of heart failure is brought to the emergency department with shortness of breath and chest pain.
Which route of administration would be most appropriate for furosemide (Lasix), a diuretic that can help to reduce fluid volume

6. overload?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
7. A 10-year-old girl with pneumonia is admitted to the hospital. Which route of administration would be most appropriate for
ceftriaxone (Rocephin), an antibiotic that can be used to treat pneumonia?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
8. A 30-year-old man who has just undergone surgery is experiencing severe pain. Which route of administration would be most
appropriate for morphine, a narcotic pain reliever?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
9. A 60-year-old woman with diabetes is unable to take her insulin tablets by mouth due to nausea and vomiting. Which route of
administration would be most appropriate for her insulin?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
10. A patient is scheduled to receive a vaccine. Which route of administration is typically used for vaccines?
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
Answers:
1. C

7. 2. C
3. C
4. D
5. D
6. C
7. C
8. C
9. B
10. D
Clinical Correlation questions things you must take note:
* Furosemide (Lasix) is a diuretic that is used to reduce fluid volume overload. It is typically administered intravenously in emergency
situations to achieve a rapid onset of action.
* Ceftriaxone (Rocephin) is an antibiotic that is used to treat a variety of infections, including pneumonia. It is typically administered
intravenously in hospitalized patients to achieve high blood levels of the drug.
* Morphine is a narcotic pain reliever that is used to treat severe pain. It is typically administered intravenously in hospitalized
patients to achieve a rapid onset of action and effective pain relief.
* Insulin is a hormone that is used to treat diabetes. It can be administered orally, but it is more commonly administered
subcutaneously to achieve better blood sugar control.
* Vaccines are typically administered subcutaneously or intramuscularly.
To make it more fun and educative there you go gunner: 10 more clinical correlate questions on the effect of
route of administration on drug action:
1. A 5-year-old child with a fever is brought to the emergency department. Which route of administration would be most appropriate
for acetaminophen (Tylenol), a fever reducer and pain reliever?
2. A 25-year-old woman with an allergic reaction to bee stings is prescribed epinephrine (EpiPen) auto-injector. Which route of
administration is used for epinephrine auto-injectors?
3. A 40-year-old man with a seizure disorder is prescribed lorazepam (Ativan). Which route of administration would be most

8. appropriate for lorazepam in the event of a seizure?
4. A 60-year-old woman with cancer is prescribed chemotherapy. Chemotherapy drugs are typically administered by which route of
administration?
5. A 35-year-old man with a chronic pain condition is prescribed fentanyl patches. Fentanyl patches are administered by which route
of administration?
6. A 70-year-old woman with diabetes is prescribed insulin. Which route of administration would be most appropriate for insulin in a
patient with diabetes who is having a hypoglycemic episode (low blood sugar)?
7. A 2-year-old child with asthma is prescribed albuterol inhaler. Albuterol inhalers are administered by which route of administration?
8. A 45-year-old man with heart failure is prescribed digoxin (Lanoxin). Digoxin can be administered orally, but it is more commonly
administered by which route of administration to achieve better blood levels of the drug?
9. A 50-year-old woman with Parkinson's disease is prescribed levodopa. Levodopa can be administered orally, but it is more
commonly administered with carbidopa (Sinemet) by which route of administration to reduce the side effects of levodopa?
10. A 65-year-old man with chronic obstructive pulmonary disease (COPD) is prescribed ipratropium bromide and albuterol sulfate
combination inhaler (Combivent). Combivent inhalers are administered by which route of administration?
Answers
1. Oral
2. Intramuscular
3. Intravenous or buccal
4. Intravenous
5. Transdermal (topical)
6. Intravenous or intramuscular
7. Inhalation
8. Intravenous
9. Oral
10. Inhalation.
Before you leave the Document Gunner
Here are 10 more clinical correlate MCQ questions on the effect of route of administration on drug action, with visible diagrams:
Question 1

9. Which of the following routes of administration is most appropriate for insulin in a patient with diabetic ketoacidosis (DKA)?
Answers:
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
The Answer is: C

10. *Explanation:
Intravenous administration of insulin is the most appropriate route in patients with DKA because it provides the fastest onset of
action.
Question 2
Which of the following routes of administration is most appropriate for epinephrine in a patient with anaphylaxis?
[Image of a diagram showing epinephrine injection into the thigh muscle]
Answers:

11. A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
The Answer is D
*Explanation:
Intramuscular administration of epinephrine is the most appropriate route in patients with anaphylaxis because it provides a rapid
onset of action and is easy to administer in an emergency setting.
Question 3
Which of the following routes of administration is most appropriate for nitroglycerin in a patient with acute myocardial infarction
(AMI)?

12. [Image of a diagram showing nitroglycerin sublingual tablet]
Answers:
A. Oral
B. Sublingual
C. Intravenous
D. Intramuscular
The Answer is B
*Explanation:
Sublingual administration of nitroglycerin is the most appropriate route in patients with AMI because it provides a rapid onset of
action and is easy to administer.
Question 4
Which of the following routes of administration is most appropriate for antibiotics in a patient with sepsis?

13. [Image of a diagram showing intravenous antibiotic infusion]
Answers:
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
The Answer is C
*Explanation:
Intravenous administration of antibiotics is the most appropriate route in patients with sepsis because it provides the fastest onset
of action and achieves high blood levels of the drug.
Question 5
Which of the following routes of administration is most appropriate for chemotherapy drugs in a patient with cancer?

14. Answers:
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
Answer is C
*Explanation:
Intravenous administration of chemotherapy drugs is the most appropriate route because it provides the fastest onset of action and
achieves high blood levels of the drug.
Question 6
Which of the following routes of administration is most appropriate for vaccines in a child?

15. Answers:
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
The Answer is B
*Explanation:
Subcutaneous administration of vaccines is the most appropriate route in children because it is safe and effective.
Question 7
Which of the following routes of administration is most appropriate for pain relievers in an elderly patient?
Answers:

16. A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
The Answer is A
*Explanation:
Oral administration of pain relievers is the most appropriate route in elderly patients because it is convenient and easy to administer.
Question 8
Which of the following routes of administration is most appropriate for anticonvulsants in a patient with status epilepticus?

17. Answers:
A. Oral
B. Subcutaneous
C. Intravenous
D. Intramuscular
The Answer is C
*Explanation:
Intravenous administration of anticonvulsants is the most appropriate route in patients with status epilepticus because it provides
the fastest onset of action and achieves high blood levels of the drug.
RESULTS FOR THE LAB.
Sodium Pentobarbital (6mg/ml) Sodium Thiopental (10mg/ml)
Group 1A
Sodium
Pentobarbital
Route of
Admin.
Latent Time
Time
Asleep
Period of
Sleep
Group 1B
Sodium
Thiopental
Route of
Admin.
Latent Time
Time
Asleep
Period of
Sleep
Injection
Time
Onset
Time
Injection
Time
Onset
Time
I.P. 13:30 13:33 13:36 108minutes I.P. 13;48 13;51 13;52 Over 90mins
13:38 13:39 13:43 38minutes 15;50 13;52 13;53 Over 90min
Sub. C 13:40 13:41 13:46 62minutes Sub. C 13;44 13;46 13;50 Over 90min
13:44 13:46 13:54 86minutes 13;46 13;49 13;50 Over 90min
Oral 13:50 13:55 13:55 7minutes Oral 13;33 13;35 13;40 Over 90min
13:50 13:54 13:57 72minutes 13;40 13;42 13;40 Over 90min
Group 2A
Sodium
Pentobarbital
I.P.
(2)
13:32 13:33 13:41 101 minutes
Group 2B
Sodium
Thiopental
I.P. 13;27 13;28 13;30 Over 90min
13:41 13:43 13:48 DEAD at 14:31 13;30 13;30 13;31 Over 90min
Sub. C 13:43 13:47 13:50 103 minutes Sub. C 13;33 13;37 13;54 Over 90min
13:44 13:48 13:50 102 minutes 13;35 13;38 13;53 Over 90min

18. Oral 13:46 13:52 13:53 102 minutes Oral 13;37 13;38 13;55 Over 90min
13:48 13:52 13:54 102 minutes 13;39 13;41 13;42 Over 90min
Group 3A
Sodium
Pentobarbital
I.P. 13:30 13:32 13:35 Over 100 min
Group 3B
Sodium
Thiopental
I.P. 13;45 13;46 13;47 Over 90min
13:28 13:30 13:39 Over 100 min 13;51 13;52 13;54 Over 90min
Sub. C 13:35 13:39 13:43 Over 100 min Sub. C 13;41 13;46 14;00 Over 90min
13:32 13:36 13:42 Over 100 min 13;43 13;43 13;44 Over 90min
Oral 13:41 13:45 13:54 Over 100 min Oral 13;34 13;35 13;36 Over 90min
13:44 13:50 13:55 Over 100 min 13;32 13;33 13;34 Over 90min
Group 4A
Sodium
Pentobarbital
I.P. 13:33 13:35 13:36 Over 90min
Group 4B
Sodium
Thiopental
I.P. 13:33 13:34 13:37 120min
13:34 13:37 13:38 Over 90min 13:34 13:36 13:38 119min
Sub. C 13:37 13:42 13:51 79 min Sub. C 13:31 13:37 13:47 110min
13:39 13:43 13:47 Over 90min 13:32 13:39 13:54 93min
Oral 13:43 13:48 13:55 65 min Oral 13:38 13:48 NS NS
13:45 13:48 13:55 73 min 13:40 13:49 NS NS
Group 5A
Sodium
Pentobarbital
I.P. 13:35 13:36 13:42 117min
Group 5B
Sodium
Thiopental
I.P. 13:38 13:40 13:45 Over 100min
13:37 13:38 13:42 117min 13:36 13;38 13:45 Over 100 min
Sub. C 13:40 13:43 13:55 104min Sub. C 13:35 13:37 13:44 Over 100 min
13:43 13:46 14:07 44min 13:33 13:35 13:39 Over 100 min
Oral 13:49 13:55 NA NA Oral 13:31 13:41 14:55 21 min
13:49 13:54 NA NA 13:29 13:38 NS N/A