What is meant by pharmacodynamics?
The effect of a drug on the body - i.e. Cellular effects
The effect of the body on a drug - i.e. Administration Distribution Metabolism Excretion
What are the four main drug action targets?
Receptors
Enzymes
Carrier molecules
Ion channels
Vesicles
Ribosomes
Which of the following are true?
Agonists activate receptors as an endogenous substrate would
Antagonists block the action of agonists
An orthosteric drug binds at the same site as a substrate
An allosteric drug binds away from the substrate site
Drugs cannot act as false substrates in enzymes
Which of the following are the characteristics of a Class II nuclear receptor?
Present in the nucleus, form heterodimers, the ligands are lipids
Present in the nucleus, form homodimers, ligands are carbohydrates
Present in the cytoplasm, form homodimers, the ligands are endocrine
Present in the cytoplasm, form homodimers, the ligands are lipids
Which of the following describes a graded dose-response?
The response of a particular system measured against agonist concentration
The drug doses required to produce specified response determined in each member of a population
Bmax is a measure of receptor saturation and is the maximum amount of drug which can bind specifically to the receptors in a membrane preparation.
Potency is the amount of a drug needed to produced a given effect, it is measured using the EC50. The greater the EC50 the greater the potency.
Which of the following is incorrect?
Efficacy is the maximum effect an agonist can produce regardless of dose
A full agonist has a high efficacy and AR* is likely, even while occupying a small number of receptors
A partial agonist has a lower efficacy and AR* is less likely despite occupying the maximum number of receptors
Inverse agonists have a higher affinity for AR* state than for AR state, it produces an effect opposite to that of an agonist, yet binds to the same receptor binding-site.
What is the meaning of tachyphylaxis?
Desensitisation of receptors with repeated administration
Amplification of a response means a fraction of receptors are needed to elicit a maximal response
The equilibrium dissociation constant, the same for any given receptor and drug combination
The process by which a drug is transported in place of an endogenous substrate or inhibit their transport
All of them
A competitive antagonist can be overcome with increasing agonist concentration. Curve: parallel shift to the right
An irreversible antagonist forms covalent bonds with the receptor. Curve: parallel shift to the right and reduced maximal asymptote
A non-competitive antagonist has signal transduction effects rather than receptor effects. Curve: reduces slope and maximum of curve
Antagonists have no efficacy and AR* doesn't exist
What is the equation for dose ratio?
(agonist + antagonist EC50) / agonist EC50
(agonist - antagonist EC50) / agonist EC50
(agonist + antagonist EC50) * agonist EC50
(agonist + antagonist EC50) / antagonist EC50
The therapeutic index (TI) is a comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes toxicity. Risk: benefit ratio = TD50 / ED50 = Toxic dose / Efficient therapeutic dose
Lipid soluble compounds cross cell membranes less easily and are therefore less rapidly absorbed
Which of the following is referring to Ka?
Determined by the Wagner-Nelson method, the higher the Ka the higher the rate of absorption, this affects Cmax.
Determined by the Wagner-Nelson method, the higher the Ka the higher the rate of absorption, without affecting Cmax.
Determined by the Schild plot, the higher the Ka the higher the rate of absorption, this affects Cmax.
Determined by the Wagner-Nelson method, the higher the Ka the lower the rate of absorption, without affecting Cmax.
Which of the following drug administration routes would be used for a drug that is poorly absorbed and unstable in the GI tract, it also gives the most control over the delivered dose and has a rapid onset of action.
Parenteral route
Vaginal route
Transdermal route
Sublingual route
Inhaled route
Which of the following are pharmacological parameters?
Cmax - max concentration of a compound after administration
Tmax - the time at which Cmax is reached
AUC - a measure of systemic exposure (area under curve / time of curve)
Bioavailability (F) - the extent of absorption after extravascular administration
Volume of distribution (Vd) - the amount of a compound in the body vs. plasma concentration
Clearance (CL) - the volume of plasma cleared of compound per unit of time
Ke - elimination rate constant
The half life of a drug in the plasma is not the elimination half life of the drug from the tissues
Which of the following are plasma proteins that bind drugs making them stay in systemic circulation rather than distributing into tissues or organs.
Albumin (HSA) - produced by the liver, binds acidic and neutral drugs
Alpha-1-acid glycoprotein (AAG) - produced by the liver, binds basic and neutral drugs
Albumin (HSA) - produced by the spleen, binds acidic and neutral drugs
Alpha-1-acid glycoprotein (AAG) - produced by the liver, binds basic and acidic drugs
Which enzymes carry out phase II metabolism?
UDP - glucuronosyl transferases (UGTs)
Cytochrome P450 family
The half life of a drug is the time it takes for the concentration of the compound to reach 50% of its current value, what is the formula to calculate it?
Half life = 0.693 / Ke
Half life = 0.693 / CL
Half life = 0.963 / Ka
Half life = 0.936 / F
Which of the following are correct when describing the cytochrome P450 enzyme family?
They are heme co-factor containing enzymes
They are individually referred to as isozymes
They are always found in the ER of the cell regardless of the organ/tissue
They are mainly found in the liver (hepatocytes) and intestines (enterocytes)
Enzyme inhibition = decreased metabolism and decreased drug exposure
Enzyme induction = increased gene transcription, increased metabolism and decreased drug exposure
What is the name given to the conjugation reaction that occurs with an endogenous substrate if phase I metabolites are too lipophilic to be retained in the kidney tubular fluid?
Glucuronidation
Acidification
Glucomodification
Metabolishment
Glomerular Filtration
Which of the following compounds enter phase II metabolism directly?
Those containing -OH
Those containing -NH2
Those containing -COOH
Those containing -SS
Those containing -C2H6
Which of the following systems involves NA as well as ACh?
Sympathetic nervous system: short preganglionic nerves and long postganglionic nerves
Parasympathetic nervous system: long preganglionic nerves and short postganglionic nerves
Somatic nervous system: neuromuscular junction
Which of the following are G protein linked (metabotropic) receptors?
muscarinic receptors (mACh) - M1,2,3 found in postganglionic parasympathetic synapses
nicotinic receptors (nACh) - Neuronal type found in the brain and autonomic ganglia
nicotinic receptors (nACh) - Muscle type found in the neuromuscular junction
Which of the following causes nervous system confusion and are therefore not clinically useful?
Neuronal type nicotinic agonists and antagonists
Muscle type nicotinic agonists and antagonists
Which of the following cause a depolarising block and can therefore be used in surgery to cause temporary paralysis?
Nicotinic agonists (muscle type)
Nicotinic antagonists (muscle type)
Nicotinic agonists (neuronal type)
Nicotinic antagonists (neuronal type)
The release of which neurotransmitter is blocked by botulinium toxin causing motor and parasympathetic paralysis?
Acetylcholine
Serotonin
Botulin
Noradrenaline
Adrenaline
Histamine
Dopamine
ACh metabolism by acetylcholineesterase is inhibited by what?
Neostigmine
Botulinium toxin
Choline
Acetyl hydroxylase
Lipolysis
Salbutamol
What are the enzymes involved in the conversion of Tyrosine to Noradrenaline?
Tyrosine Hydroxylase
DOPA decarboxylase
DA -B-hydroxylase
Tyrosine decarboxylase
DA decarboxylase
L-DOPA Hydrogenase
Which of the following are true about noradrenergic receptors?
They exist as A1,2 and B1,2,3
They exist as A1,2,3 and B1,2
They are G protein coupled
They are tyrosine kinase receptors
They are found in the effector tissues of the sympathetic system
They are found in the effector tissues of the parasympathetic system
Which of the following is a negative feedback presynaptic receptor?
A1 noradrenergic receptor
A2 noradrenergic receptor
B1 noradrenergic receptor
B2 noradrenergic receptor
B3 noradrenergic receptor
Which drug given subcut can prolong and isolate local anaesthesia and by what mechanism?
Adrenaline by A1 mediated vasoconstriction
Adrenaline by B1 mediated vasoconstriction
Noradrenaline by A1 mediated vasodilation
Salbutamol bt A2 mediated vasoconstriction
Botulinium toxin by A1 mediated vasodilation
Which of the following are noradrenergic agonists?
Clonidine - A2
Dobutamine - B1
Prazosin - A1
Salbutamol - B2
Atenolol - B1
Timolol - B2
What is the pathway of the false substrate that decreases overall noradrenergic neurotransmission?
meDOPA > meDA > meNA
meDOPA > meNA > meDA
L-DOPA > L-DA > L-NA
DA > DOPAC > HVA
Tyrosine > DOPA > DA > NA
What is the name of the drug that disrupts storage of NA in synaptic vesicles?
Reserpine
Dobutamine
Atenolol
MAOI
COMT
NA reuptake inhibitors
Which of the following is not involved in the regulation of airway smooth muscle?
Parasympathetic bronchoconstriction and mucus secretion
Circulating adrenaline causing bronchodilation
Nonadrenergic Noncholinergic transmitters e.g. inhibitory NO or excitatory substance P or neurokinin A
Sensory receptors - chemical and physical stimuli
Circulating dopamine causing broncoconstriction
Which of the following is the delayed phase of asthma?
Bronchoconstriction
Inflammation/Damage in response to mediators
Glucocorticoids suppress the immune system and therefore are good at treating the delayed phase of asthma. Which of the following do they decrease the production of?
LTC4, LTD4 - spasmogens
LTB4 - chemotaxins
PGE2, PGI2 vasodilators, cytokines
LTC4 - chemotaxins
LTB4, LTC4, - spasmogens
PGE5, PGL2, chemotaxins
Where is the cough centre located?
Hypothalamus
Oesophagus
Adrenal medulla
Cerebral cortex
Which of the following are true of local anaesthetics?
1. block electrical signalling in neurones by blocking voltage gated NA+ channels 2. Interact with A subunit and plug the inner end of the transmembrane pore 3. Binds in the ionised (hydrophilic) form 4. Unionised form gains acess through nerve sheath and axon membrane 5. Most are weak bases 6.Duration of action is limited by hydrolysis of ester/amide bond
1. block electrical signalling in neurones by blocking voltage gated NA+ channels 2. Interact with A subunit and plug the inner end of the transmembrane pore 3. Binds in the ionised (hydrophilic) form 4. Ionised form gains acess through nerve sheath and axon membrane 5. Most are weak bases 6.Duration of action is limited by hydrolysis of disulphide bonds
1. block electrical signalling in neurones by blocking voltage gated NA+ channels 2. Interact with B subunit and plug the inner end of the transmembrane pore 3. Binds in the ionised (hydrophilic) form 4. Unionised form gains acess through nerve sheath and axon membrane 5. Most are weak acids 6.Duration of action is limited by hydrolysis of ester/amide bond
1. block electrical signalling in neurones by blocking voltage gated K+ channels 2. Interact with A subunit and plug the inner end of the transmembrane pore 3. Binds in the unionised (hydrophobic) form 4. Ionised form gains acess through nerve sheath and axon membrane 5. Most are weak bases 6.Duration of action is limited by hydrolysis of disulphide bonds
Antidysrhythmic drugs treat disturbances of cardiac rhythm and consist of...
Class I blocking sodium channels and Class II blocking calcium channels
Class I blocking calcium channels and Class II blocking sodium channels
Class I blocking sodium channels and Class II blocking potassium channels
Class I blocking potassium channels and Class II blocking calcium channels
What do anticonvulsant drugs target?
Voltage gated sodium channels
Ligand gated sodium channels
Voltage gated potassium channels
G protein receptors
Tyrosine kinase receptors
Which condition is categorised by the degeneration of DAergic neurones of the nigrostriatal tract and loss of DA transmission in striatum via D2 receptors?
Parkinson's disease
Depression
Paralysis
Psychosis
Hyperthyroidism
Cushing's syndrome
Which of the following enzymes are found in the conversion of tyrosine to dopamine?
Tyrosine hydroxylase
DA B-hydroxylase
DOPA hydroxylase
Carbonic Anhydrase
The metabolism of DA sees it converted to DOPAC and then HVA, catalysed by which enzymes?
Monoamine oxidase, then Aldehyde Dehydrogenase, then Catechol-O-methyl transferase
Aldehyde Dehydrogenase, then Catechol-O-methyl transferase, then Monoamine oxidase
Monoamine oxidase, then Aldehyde Decarboxylase, then Catechol-O-methyl transferase
Which of the following are true of DA receptors?
They are G protein linked
They are ligand gated ion channels
D2-like receptors are inhibitory D1-like receptors are excitatory
D1-like receptors are inhibitory D2-like receptors are excitatory
Inhibitory receptors inhibit adenylate cyclase or open K+ channels
Excitatory receptors stimulate adenylate cyclase
Inhibitory receptors inhibit DOPA decarboxylase
Excitatory receptors stimulate adenylate cyclase or open K+ channels
In the treatment of Parkinson's disease, giving L-DOPA and a decarboxylase inhibitor (carbidopa) would have what effect?
Increase dopamine
Decrease dopamine
Increase DOPA decarboxylase
Increase reuptake by DAT
Increase transport of DA into vesicles by VMAT
What is the name and action of a MAO inhibitor?
Selegiline - inhibits MAO-B, increasing the DA content of vesicles
Selegiline - inhibits MAO-B, decreasing the DA content of vesicles
Carbidopa - inhibits MAO-A, increasing the DA content of vesicles
Prazosin - inhibits MAO-B, increasing the DA content of vesicles
Which of the following neural pathways are thought to be involved in the development of depression?
Locus coeruleus contains cell bodies with projections to the mid brain and the hypothalamus, and the hippocampus and cortex
Dorsal and median raphe nuclei contain cell bodies with projections to the hypothalamus, hippocampus and cortex
Dorsal and median locus coeruleus contain cell bodies with projections to the cerebral cortex, hypothalamus and adrenal medulla
Locus coeruleus contains cell bodies with projections to the andrenal medulla, cortex, and dorsal ventricular brain centre
Which of the following is the correct pathway for 5-HT synthesis?
Tryptophan (Tryptophan hydroxylase) > 5-HTP (5-HTP decarboxlase) > 5-HT
Tryrosine (Tyrosine hydroxylase) > 5-HTP (5-HTP decarboxlase) > 5-HT
Tryptophan (Tryptophan decarboxylase) > 5-HTP (5-HTP hydroxylase) > 5-HT
Tryptophan (Tryptophan hydroxylase) > 5-HTS (5-HTS decarboxlase) > 5-HT
Tryptophan (5-HTP decarboxlase) > 5-HTP (5-HT hydroxylase) > 5-HT
What is the end product in the metabolism of 5-HT?
5-HIAA
5-HTP
Tryptophan
DA
NA
5-HITP
What is the last enzyme involved in NA metabolism and what is the final product?
Catechol-O-methyl transferase producing MHPG
Catechol-O-methyl transferase producing DOPEG
Monoamine Oxidase producing MHPG
Aldehyde dehydrogenase producing 5-HIAA
Monoamine Oxidase producing DOPAC
Catechol-O-methyl transferase producing HVA
Which of the following is a ligand gated ion channel?
5-HT-3
5-HT-1(A-F)
5-HT-2(A-C)
Which of the following autoreceptors can be found on the cell body?
NA A2 and 5-HT-1B
NA A2 and 5-HT-1A
NA A1 and 5-HT-1B
5-HT-1A and 5-HT-1B
Which of the following is the action of oestrogen?
Sensitises LH releasing cells, proliferation of endometrium, inhibits release of FSH
Renders endometrium suitable for the implantation of an ovum, inhibits release of FSH, LH and GRH
Inhibits GRH, sensitises FSH releasing cells, proliferation of endometrium
Renders endometrium suitable for the implantation of an ovum, inhibits release of FSH, sensitises LH releasing cells
Blocking of which hormones induces a pharmacological menopause?
FSH
LH
GRH
Progesterone
Oestrogen
human chorionic gonadotropin
What is the action of prolactin?
Released from anterior pituitary, acts on hypothalamus preventing GRH release
Released from hypothalamus, acts on anterior pituitary preventing GRH release
Released from anterior pituitary, acts on hypothalamus preventing FSH release
Released from hypothalamic nuclei, acts on mammary tissue preventing LH release
Which of the following are symptoms of inflammation?
Warmth
Pain
Oedema (swelling)
Erythema (redness)
Oedema (redness)
Erythema (swelling)
Inc dopamine
Dec immune response
Which of the following are vasoactive mediators that will increase vascular permeability leading to oedema?
histamine
5HT
Leukotrienes
Prostaglandins
Platelet activating factor (PAF)
C5a
LTB4
Cytokines
What do non-steroidal anti-inflammatory drugs (NSAIDs) do?
inhibit cyclooxygenase activity, decreasing the formation of prostanoids
inhibit cyclooxygenase activity, increasing the formation of prostanoids
inhibit cyclooxygenase activity, increasing the formation of eicosanoids
stimulate cyclooxygenase activity, decreasing the formation of prostanoids
stimulate cyclooxygenase activity, increasing the formation of prostanoids
Which of the following are actions of steroidal anti-inflammatories?
Dec synthesis of prostanoids through inhibition of phospholipase 2
Dec prostaglandin-H-synthase transcription
Dec cytokines
Inhibit cyclooxygenase activity
Suppression of the immune system
Which of the following are true of histamine?
Synthesised from the amino acid Histidine
Synthesised from the amino acid tyrosine
Stored in granules in mast cells and basophils
Stored in vesicles in macrophages
Released by the complement system and IgEs
Released by IgMs
G protein coupled receptors: H1-4
Tyrosine Kinase receptors: H1-2
What is the meaning of selective toxicity?
Agents that destroy parasites while being relatively non-toxic to the host
Agents that destroy the majority of pathogens without disturbing host cells
Agents that selectively destroy particular parasites
Agents that can target cells of specific organs in order to kill tumour cells
Which of the following is not a major class of antibiotics?
Penicillins
Sulphonamides
Fluoroquinolones
Macrolides
Tetracyclines
Quinolides
Metastasis is the development of secondary malignant growths at a distance from a primary site of cancer
Which of the following is false?
Platinum based drugs cross link DNA with other bases and proteins damaging it
Carboplatin has the same mechanism as cisplatin with fewer side effects
Daunorubicin is an antibiotic used to treat cancer, blocking the enzyme that normally untangles strands of DNA
The Philadelphia translocation results in the genes BCR and abl being joined, switching off cell division by activating other proteins
Imatinib inhibits the BCR-abl protein kinase
The Philadelphia translocation occurs on which chromosomes and in which disease?
9 and 22, Chronic Myeloid Leukemia
9 and 23, Acute Lymphoblastic Leukemia
9 and 22, Parkinsons
8 and 22, Chronic Myeloid Leukemia
Which of the following species of malaria has the quickest onset and is the most severe?
P. falciparum
P. malarie
P. Vivax
P. Ovale
P. Sporozoa
Which stage of the life cycle are plasmodiums at when they re-enter the liver and lay dormant?
Sporozoites
Gametocytes
Meterozoites
Trophozoites
Drug therapy for malaria takes the forms of radical cure, clinical cure and prophylaxis. Which of the following is not a category of anti-malarial drugs?
4-aminoquinolines
Quinine-methanols
8-aminoquinolines
Antifolates
Hydroxynapthoquinone
What is the treatment for paracetamol overdose longer than one hour after ingestion?
Activated charcoal
N-acetylcysteine (NAC)
Glutathione infusion
Sulphate bypass
NAPQI
A secondary adverse effect of a drug is indirectly caused, secondary to the drug
Who is least at risk of adverse drug reactions?
Adults
Neonates
Children
Elderly
People on medication
Females
Which of the following are correct?
Type A drug reaction: Augmented pharmacological effect
Type B drug reaction: Basic - predictable on basis of pharmacology of the drug
Type C drug reaction: Chronic effects - occur after prolonged treatment
Type D drug reaction: Delayed, effects occur remote from treatment (or in the child of the treated)
Type E drug reaction: Expected - common side effects of a drug
Addiction imbalances involve which two areas of the brain?
Amygdala (Impulsive)
Pefrontal cortex (Reflective)
Prefrontal cortex (Impulsive)
Amygdala (Reflective)
Hypothalamus (Impulsive)
Anterior pituitary (Reflective)
Hypothalamus (Reflective)
Which of the following are correct when measuring addiction?
There are a total of 11 addictive traits on the scale
There are a total of 9 addictive traits on the scale
Mild = 2/3 symptoms
Mild = 1-4 symptoms
Moderate = 4/5 symptoms
Moderate = 5/6 symptoms
Severe = 6+ symptoms
Severe = 7+ symptoms
ADH is released from the posterior pituitary in response to low blood volume/pressure or high osmolarity and acts upon the kidney to cause water reabsorption, increasing blood volume
Which form of diabetes is categorised by copius hypotonic urine resulting from decreased ADH secretion?
Diabetes Mellitus
Diabetes Insipidus
Which parts of the brain does cortisol have negative feedback on and what effect does this have on the hormones they produce?
Hypothalamic nuclei, decreasing CRH Anterior pituitary, decreasing ACTH
Hypothalamic nuclei, decreasing ACTH Anterior pituitary, decreasing CRH
Adrenal cortex, decreasing CRH Anterior pituitary, decreasing ACTH
Anterior Pituitary, decreasing CRH Adrenal Cortex, decreasing ACTH
Which of the following are under tropic control?
ADH
ACTH
Cortisol
CRH
Insulin
Which of the following are actions of cortisol?
Inc. and maintains normal glucose levels in blood
Dec. protein synthesis
Inc. gluconeogenesis
Dec. glucose uptake into muscle and adipose tissue
Inc. protein synthesis and dec. lipolysis
Inc. glucogenolysis
Dec. and maintain glucose levels in the blood
Which of the following inhibits cortisol synthesis by blocking 11B-hydroxylating enzyme?
Metyrapone
Albumin
Creatinine
Glucocorticoids
What is the definition of tropic control?
Hormone released in response to stimulation from another hormone
Hormone released directly in response to neural stimulation
Hormone directly influenced by circulating blood levels of substrate that the hormone itself controls
What do sulphonylureas do?
Increase insulin secretion from B cells by blocking K-ATP channels (causing depolarisation)
Increase insulin secretion from B cells by blocking K-ATP channels (causing hyperpolarisation)
Decrease insulin secretion from A cells by opening K-ATP channels (causing depolarisation)
Decrease insulin secretion from B cells by blocking Na-ATP channels (causing depolarisation)
Decrease insulin secretion from B cells by blocking K-ATP channels (causing depolarisation)
If there is fertilisation of the egg, what hormone does the ovum secrete?
Human chorionic gonadotrophin
Human chorionic gonadotrophin and oestrogen
Which of the following drugs are used to aid fertility?
GRH agonists
GRH antagonists
Mefipristone
Oestrogen and progesterone pill
FSH agonists
Which of the following innate responses to inflammation occurs 8hrs-6days after injury?
Systemic effects
Microvascular events
Mediator release
Healing
Inflammatory cell accumulation
What is the purpose of chemotactic factors e.g. C5a, LTB4, Cytokines?
Recruitment of inflammatory cells leading to inflammation
Increased vascular permeability
Dilation of arterioles increasing blood flow to site
Constriction of venules decreasing blood flow away from site
Production of oedema
Monocytes arrive before leucocytes and transform into macrophages, producing mediators, removing microorganisms/debris and secreting lipocortin
What do vascular endothelial cells secrete that causes the smooth muscle in the area of inflammation to relax?
NO
Eicosanoids
PAF
NSAIDS preferentially target PGHS1
What is a short term side effect of glucocorticoid therapy?
Hyperglycemia
Hypoglycemia
Hypertension
Gastric acid secretion is coupled with which histamine receptor?
H1
H2
H3
H4
Which of the following is an action that both H3 and H4 receptors share?
Decrease intracellular cAMP
Increase intracellular cAMP
Activate proton pump
Adenyl cyclase coupled
Phospholipase C coupled
Which of the following are associated with Penicillin's?
Examples include: Ampicillin, Amoxycillin (developed to have an improved duration)
Examples include: Ciprofloxacin and Streptogramins
Early forms were effective against gram positives and only a few gram negatives
Early forms were effective against gram negatives and gram positives
Expanded spectrum versions are effective against pseudomonads
Reversed spectrum versions have greater activity on gram positives
Can exist in B-lactamase resistant forms (Fludoxacillin)
Excreted by the kidney in levels that can be reduced by probenecid
Excreted in the bile in levels that can be increased by N-acetylglucosamine
Inhibit transpeptidases that establish cross links in peptidoglycan from N-acetylmuramic acid causing bacteria to swell and rupture (bacteriocidal)
Which of the following are true of sulphonamides?
Selectively targets metabolic pathways: Folate biosynthesis
Targets prokaryotic ribosomes and protein synthesis
Bacteriocidal
The normal substrate the drugs block is PABA
Their use is declining outside dentistry
Oral administration is given as protected tablets to prevent them being inactivated by gastric juice
Which of the following are Tetracyclines?
Bacteriostatic
Half life of 30-80 minutes
Half life of 6-18 hours
Use is declining outside of dentistry
Excreted in the kidney and the bile
Interrupts the termination phase of protein synthesis in bacterial ribosomes
Don't usually enter the CSF (unless meninges inflammation)
Which of the following is true of fluoroquinolones?
They are based on naladixic acid
Target DNA replication via type II topoisomerases
Examples include ciprofloxacin
Target protein synthesis
Inhibitor of CYP1A2
Inhibits DNA gyrase in gram positives and DNA topoisomerase IV in gram negatives
Examples include streptogramins and lincosamides
Which of the following is true of macrolides?
Streptogramins such as erythromycin are effective for gram positives and spirochaetes but not gram negatives
Lincosamides such as clindamycin are effective for gram positive cocci and anaerobes
Target 30S ribosomal subunit
Block translocation of newly forming peptide by binding to site near RNA exit tunnel causing peptidyl-transferase RNA drop off
Administered IV to bypass metabolism in the stomach
Administered orally in protected tablets
Excreted in the kidneys
Crosses the placenta but not the blood brain barrier
Do not enter the CSF
Metabolised by demethylation (CYP3A4)