Part 12
General revision&Questions
Questions and answers
1-Name two intravenous anaesthesia and mention their side effects
Apnea, laryngospasm & bronchospasm
Pain
Thrombophlebitis at the site of injection.
2- Mention the contraindication of morphine
Morphine is contraindicated in the following cases:
1- very old & very young persons
2- acute abdominal pain
3- liver & respiratory diseases
4- During labor & lactation
5- Biliary colic & pancreatitis.
3- Mention the mechanism of action of aspirin as analgesic and anti-inflammatory:
The mechanism of action of aspirin :
1- central it decreases the level of PG leading to increased pain threshold.
2- Peripheral
decrease also the level of PG --- increased the sensitivity of pain receptors to anti inflammatory mediators as 5HT , histamine.
4- Mention the clinical uses of diazepam
1- Treatment of anxiety
2- Sedative & hypnotic in insomnia
3-Muscle spasm & rigidity
4-Epilepsy & status epilepticus
5- Preanaesthetic medication
6- Treatment of alcohol withdrawal
5-Mention the side effects of monoamine oxidase inhibitors(MAO)
The side effects of MAO :
1- CNS: tremors , insomnia , confusion , convulsions , fatigue.
2- Genito urinary system: difficulty of micturation , inhibition of ejaculation
3- CVS: postural hypotension
4- Hepatocellular damage , optic nerve damage.
6- Bound fraction of a drug
This part is pharmacologically inactive & is not substrate for metabolism ,excretion &acts as reservoir.
7- Mention the clinical uses & side effects of ciprofloxacin
Clinical uses:
Ciprofloxacin is used to treat infections of the skin, lungs, airways, bones, and joints caused by susceptible bacteria as pseudomonas, neisseria gonorrhea , salmonella , shigella , haemophilus influenza. Ciprofloxacin is also frequently used to treat urinary infections caused by bacteria such as E. coli.
Side effects:
Nausea, vomiting, diarrhea, stomach pain/cramps, headache, restlessness, rash, anxiety, nightmares
8- Mention 4 drugs of different groups used in treatment of typhoid fever.
a- Acute stage of typhoid fever:
1- Chloramphenicol
2- Co – trimexazole
3- Ampicillin , amoxicillin
4- Ciprofloxacin and other quinolones and third generation of cephalosporin.
b- Carrier stage of typhoid fever:
1- Co – trimoxazole
2- Ampicillin
3- Amoxicillin
9- Explain the mechanism of action of co - trimoxazol
They are bacteriostatic. They compete with PABA for the enzyme dihydropteroate synthetase enzyme so inhibits synthesis of folic acid which is essential for bacterial growth.
10- Mention the side effects of aminoglycosides
The side effects of aminoglycosides are:
1- Ototoxicity
2- Nephrotoxicity
3- Neuromuscular blocking effect
4- contact dermatitis.
11- Give the reason for combining amoxicillin with clavulinic acid and for combining probencid with ceftriaxone:
Antibiotic combination due to:
1- Synergistic effect
2- Delay development of bacterial growth
3- Treat mixed bacterial infection
4-Broaden spectrum
5- Treat urgent infection before lab diagnosis done.
12- Hepatic enzyme inducer drugs(give 2 examples) and 2 enzyme inhibitors.
-The drug interaction of erythromycin :
It inhibits cytochrome p450 so it increases the effect of warfarin , theophylline & cyclosporine.
-Enzyme inhibitors as:
Chloramphenicol, allopurinol , oestrogen & progesterone
13- Mention the therapeutic uses of metronidazole:
Metronidazole used in the following cases:
1- Intestinal amoebiasis (acute , chronic)
2- Hepatic amoebiasis
3- Giardiasis & trichomonas infection
4- Anaerobic infection
14- Mention the clinical uses of acyclovir:
Acyclovir is used to treat infections caused by herpes viruses. illnesses caused by herpes viruses include genital herpes, cold sores, shingles, and chicken pox.
15- Mention 4 groups of different drugs used in treatment of AIDS.
1- Reverse transcriptase (RT) inhibitors. RT inhibitors interfere with the virus' reverse transcriptase enzyme that is essential for viral replication.
- 3TC (Lamivudine) , ABC (Abacavir) , AZT (Retrovir)
2- Protease Inhibitors
Protease inhibitors, or PI, also interfere with an enzyme needed for virus replication, specifically the protease enzyme.
3- Fusion Inhibitors Fusion inhibitors are some of the newest weapons in the treatment of HIV. These drugs actually change the shape of the virus' covering, preventing it from binding to and infecting cells.
4- HAART and AZT
These combinations of HIV treatments are known collectively as HAART, or Highly Active Antiretroviral Therapy.
16)-Give brief account on the following:
1-Non proprietary name of the drug
Name given to the drug after synthesis it and its same all over the world
2-Advantages of sublingual route of drug administration.
1- Rapid onset of action
2- bypass first pass metabolism
3-Removed easily
3-Disdvantages of I.V route of drug administration.
1- Allergic reaction : ex anaphylactic shock
2- Velocity reaction: ex if aminophylline is given rapidly it can produce arrhythmia, hypotension & cardiac arrest.
3- Pyrogenic reaction (fever)
4- Disease transmission
5- Thrombophlebitis (inflammation of the vein then thrombosis).
6- Extravasations (leakage) sever irritation
4- Factors affecting absorption after oral administration.
1- Motility of the stomach
2- Ph of the GIT
3-Food in the stomach
4-Bioviability of the drug
5-Bioavaliability of a drug & how it is measured.
It is the fraction of unchanged drug reaching systemic circulation following administration by any route.
It is measured by Area under the curve oral *100
Area under the curve I.V
6- Bound fraction of a drug
This part is pharmacologically inactive & is not substrate for metabolism ,excretion &acts as reservoir.
7- Volume of distribution of a drug
The volume of fluid where the drug is distributed.
Ex: plasma ,extracelluar fluid & intracellular fluidVd = M(mg)
C(mg/L)
M: Amount of the drug
C: Concentration in plasma
Drugs are usually distributed throughout the body according to their affinities for the different tissues& body compartments.
-Mepacaine "in the liver" &-Calcium in "teeth&bones"& -Arsenic "in Hair& nails".
8-Plasma half lifetime of the drug:
The time during which the peak concentration of the drug in the blood reduced to its half
9- Zero order elimination of drugs:
Rate of elimination remains constant irrespective of drug concentration . clearance decreased with increased drug concentration.
10- Spare receptors
When a drug producing its maximum effect , there will be a certain number of receptors are free
11- Partial agonist:
Drug which stimulate & block receptors
They have affinity ,efficacy and slow dissociation.
12- Hepatic enzyme inducer drugs(give 2 examples) and 2 enzyme inhibitors.
Enzyme inducers as:
Phenobarbiton, Rifampicin, androgen
Enzyme inhibitors as:
Chloramphenicol, allopurino , oestrogen & progesterone
13- Teratogenicity:
Drugs induces fetal abnormalities especially in first trimester ex: aspirin
14- Idiosyncrasy:
Abnormal reaction to drug due to genetic or enzyme defect.
15- Non competitive antagonism (give one example)
Where the antagonist can not be overcome by excess agonist
Ex:
Reversible antagonist as : succinylcholine
Irreversible antagonist as: phenoxybenzamine
16- Down regulation of receptors
Long stimulation of cell with agonist will lead to decrease volume and sensitivity of receptors.
17- Placebo drugs
Placebo are inert dosage forms which produce their effect physiologically
They are used in testing of new drugs.
18- Methods of prolonging drug action duration
1- delay absorption by :
reduction of vascularity & solubility
mixing with oil
using sustained released form
implantation of drugs
2- delay metabolism by enzyme inhibitors
3-delay excretion
4- increasing binding to plasma protein
19- Potentiation
one drug has no apparent action but potentiate = strengthen the action of another active drug
Ex: Barbiturate potentiate the analgesic action of salicylates.
20- Therapeutic index
It is a measure for safety of drugs:
The higher the index the safer he drug. = LD 50
ED 50
LD 50 = Lethal dose this dose which is fatal lead to death
ED 50 = Effective dose this dose which give the effective results .
17)- Define 2 factors affecting absorption of the drug
Factors affecting absorption of the drug:
1- The vascularity at the site of absorption
2- The ph medium .dosage , form and route of administration of the drug.
18)-Define
1- Bioavailability 2- plasma half life of a drug
-Bioavailability: It is the fraction of unchanged drug reaching systemic circulation following administration by any route.
-P
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