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  • Question 1 - Which of the following is NOT a common side effect of diazepam: ...

    Correct

    • Which of the following is NOT a common side effect of diazepam:

      Your Answer: Bradycardia

      Explanation:

      Adverse effects include:Drowsiness and lightheadednessConfusion and ataxia (especially in the elderly), amnesia, muscle weaknessHeadache, vertigo, tremor, dysarthria, hypotension, decreased libido, erectile dysfunction, gynaecomastia, urinary retentionParadoxical effects such as talkativeness, excitement, irritability, aggression, anti-social behaviour, and suicidal ideationWithdrawal symptoms, for example anxiety, depression, anorexia, impaired concentration, insomnia, abdominal cramps, palpitations, tremor, tinnitus and perceptual disturbancesTolerance and dependence (people who use benzodiazepines longer term can develop tolerance and eventual dependence)

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
      2.1
      Seconds
  • Question 2 - Which of these structures is the smallest and deepest component of muscle connective...

    Correct

    • Which of these structures is the smallest and deepest component of muscle connective tissue?

      Your Answer: Endomysium

      Explanation:

      There are three types of muscle:Skeletal muscleCardiac muscleSmooth muscleIndividual muscle is enveloped in a layer of dense irregular connective tissue called the epimysium. The epimysium protects the muscles from friction against bones and other muscles.Skeletal muscle is composed of muscle fibres, referred to as myofibers which is ensheathed by a wispy layer of areolar connective tissue called the endomysium. The endomysium is the smallest and deepest component of muscle connective tissue. Myofibers grouped together in bundles form fascicles, or fasciculi. These are surrounded by a type of connective tissue called the perimysium.Beneath the endomysium lies the sarcolemma, an elastic sheath with infoldings that invaginate the interior of the myofibers, particularly at the motor endplate of the neuromuscular junction.

    • This question is part of the following fields:

      • Basic Cellular Physiology
      • Physiology
      3.1
      Seconds
  • Question 3 - A 25-year-old man suffers from a shoulder injury that damaged the nerve that...

    Correct

    • A 25-year-old man suffers from a shoulder injury that damaged the nerve that innervates the infraspinatus muscle.Which of the following nerves may most likely be affected?

      Your Answer: The suprascapular nerve

      Explanation:

      The suprascapular nerve (C5-C6) innervates the infraspinatus. It originates at the superior trunk of the brachial plexus. It runs laterally across the lateral cervical region to supply the infraspinatus and also the supraspinatus.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      1.5
      Seconds
  • Question 4 - Captopril should not be used if you have any of the following conditions:...

    Correct

    • Captopril should not be used if you have any of the following conditions:

      Your Answer: Renal artery stenosis

      Explanation:

      Contraindications indications of Captopril include:- Bilateral renal artery stenosis- Hypersensitivity to ACE inhibitors- Anuria- History of ACEI-induced angioedema- Hereditary or idiopathic angioedema- Co-administration of Neprilysin inhibitors (e.g., sacubitril) with ACE inhibitors may increase angioedema risk; do not administer ACE inhibitors within 36 hours of switching to or from sacubitril/valsartan.If ACE inhibitors are used, they should be initiated only under specialist supervision and renal function should be monitored regularly. ACE inhibitors should also be used with particular caution in patients who may have undiagnosed and clinically silent renovascular disease. This includes patients with peripheral vascular disease or those with severe generalised atherosclerosis.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      3
      Seconds
  • Question 5 - Which of the following statements about lithium treatment is FALSE: ...

    Correct

    • Which of the following statements about lithium treatment is FALSE:

      Your Answer: Concomitant treatment with NSAIDs decreases serum-lithium concentration.

      Explanation:

      Lithium levels are raised by NSAIDs because renal clearance is reduced. Lithium is a small ion (74 Daltons) with no protein or tissue binding and is therefore amenable to haemodialysis. Lithium is freely distributed throughout total body water with a volume of distribution between 0.6 to 0.9 L/kg, although the volume may be smaller in the elderly, who have less lean body mass and less total body water. Steady-state serum levels are typically reached within five days at the usual oral dose of 1200 to 1800 mg/day. The half-life for lithium is approximately 18 hours in adults and 36 hours in the elderly.Lithium is excreted almost entirely by the kidneys and is handled in a manner similar to sodium. Lithium is freely filtered but over 60 percent is then reabsorbed by the proximal tubules.

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      2.9
      Seconds
  • Question 6 - Which of the following is NOT an effect of gastrin: ...

    Correct

    • Which of the following is NOT an effect of gastrin:

      Your Answer: Stimulation of insulin release

      Explanation:

      Gastrin acts to:Stimulate acid secretion from parietal cells (both directly and indirectly by stimulating release of histamine from ECL cells)Stimulate pepsinogen secretion from chief cellsIncrease gastric motilityStimulate growth of gastric mucosa

    • This question is part of the following fields:

      • Gastrointestinal
      • Physiology
      15
      Seconds
  • Question 7 - Regarding hypernatraemia, which of the following statements is INCORRECT: ...

    Correct

    • Regarding hypernatraemia, which of the following statements is INCORRECT:

      Your Answer: In acute severe hypernatraemia, seizures and intracranial vascular haemorrhage can occur as a result of brain cell lysis.

      Explanation:

      Acute severe hypernatraemia is a medical emergency and requires inpatient management in a high dependency setting. Seizures and intracranial vascular haemorrhage as a result of brain cell crenation can occur. The cause is most commonly excessive water loss and the key aspect of treatment is aggressive fluid replacement (typically with normal saline as this is relatively hypotonic). If urine osmolality is low, diabetes insipidus (DI )should be considered and a trial of synthetic ADH given. In patients with known DI, it is essential to ensure synthetic ADH is given parenterally and that close fluid balance is observed.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      4
      Seconds
  • Question 8 - Regarding chemical control of respiration, which of the following statements is INCORRECT: ...

    Correct

    • Regarding chemical control of respiration, which of the following statements is INCORRECT:

      Your Answer: The blood-brain barrier is freely permeable to HCO3 - ions.

      Explanation:

      CSF is separated from the blood by the blood-brain barrier. This barrier is impermeable to polar molecules such as H+and HCO3-but CO2can diffuse across it easily. The pH of CSF is therefore determined by the arterial PCO2and the CSF HCO3-and is not affected by blood pH.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      8.2
      Seconds
  • Question 9 - A somatostatinoma is diagnosed in a 74-year-old patient who has recently developed diabetes...

    Correct

    • A somatostatinoma is diagnosed in a 74-year-old patient who has recently developed diabetes mellitus, recurrent episodes of gallstones, and Steatorrhoea. She also  has a tumour in the head of her pancreas.Which of the following is the most likely effect of this tumour? 

      Your Answer: Inhibit gastric acid secretion

      Explanation:

      Somatostatin-producing cells present in the pyloric antrum, duodenum, and pancreatic islets are known as D-cells or delta-cells. Somatostatin inhibits gastric acid secretion by acting directly on acid-producing parietal cells in the stomach via a G-protein coupled receptor.Somatostatin affects hormones in the following ways:Inhibits the anterior pituitary’s secretion of growth hormone.Inhibits the anterior pituitary’s secretion of thyroid-stimulating hormone.The secretion of various gastrointestinal hormones is inhibited (including gastrin, CCK, secretin, motilin, VIP and GIP) Reduces the rate at which the stomach empties.Inhibits the release of insulin and glucagon from the pancreas.The pancreas’ exocrine secretory activity is inhibited.Somatostatin can also slow the digestive process by suppressing the production of hormones such gastrin, secretin, and histamine, which reduces gastric acid secretion.A somatostatinoma is a cancerous tumour of the endocrine pancreas’ D-cells, which make somatostatin. Somatostatin inhibits pancreatic and gastrointestinal hormones when levels are high. The following clinical characteristics are related with somatostatinomas:Insulin secretion blockage causes diabetes mellitus.Gallstones by inhibition of CCK and secretin Steatorrhoea via inhibition of CCK and secretinHypochlorhydria is caused by the suppression of gastrin, a hormone that increases gastric acid output regularly.

    • This question is part of the following fields:

      • Gastrointestinal Physiology
      • Physiology
      2.9
      Seconds
  • Question 10 - A 22-year-old student presents with severe headache accompanied with nausea and vomiting. Upon...

    Correct

    • A 22-year-old student presents with severe headache accompanied with nausea and vomiting. Upon observation and examination, it was noted that he is febrile and Kernig's sign is positive. A diagnosis of meningitis was suspected and a lumbar puncture was to be performed.Which of the following statements regarding meningitis is true?

      Your Answer: The dura mater is the outermost layer

      Explanation:

      Meningitis is defined as the inflammation of the meninges due to an infection caused by a bacteria or a virus. Symptoms usually include stiffness of the neck, headache, and fever. There are 3 meningeal layers that surround the spinal cord and they are the dura mater, arachnoid matter, and pia mater. The dura mater is the outermost and thickest layer out of all the 3 layers. The arachnoid atter is the middle layer, and is very thin.The third and deepest meningeal layer is the pia mater that is bound tightly to the surface of the spinal cord.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      2.4
      Seconds
  • Question 11 - The patient is a 66-year-old woman who has troublesome bilateral ankle swelling. This...

    Correct

    • The patient is a 66-year-old woman who has troublesome bilateral ankle swelling. This has been happening since she began taking a new antihypertensive medication a few weeks ago.Which of the following medications is most likely to be the cause of this adverse reaction?

      Your Answer: Amlodipine

      Explanation:

      Amlodipine is a calcium-channel blocker that is frequently used to treat hypertension. Ankle swelling is a very common side effect of calcium-channel blockers, and it occurs quite frequently.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      2.7
      Seconds
  • Question 12 - Where does angiotensin II directly act on the renal nephron: ...

    Correct

    • Where does angiotensin II directly act on the renal nephron:

      Your Answer: Proximal tubule

      Explanation:

      Angiotensin II acts to directly increase Na+reabsorption from the proximal tubule (by activating Na+/H+antiporters).

    • This question is part of the following fields:

      • Physiology
      • Renal
      2
      Seconds
  • Question 13 - Regarding propofol, which of the following statements is INCORRECT: ...

    Correct

    • Regarding propofol, which of the following statements is INCORRECT:

      Your Answer: A lower induction dose of propofol is required in children.

      Explanation:

      Elderly patients have a reduced volume of distribution and slower clearance of the drug. They are therefore more sensitive to the effects of propofol and the drug wears off more slowly. They need less of the drug, which should be injected slowly, monitoring its effect on the patient. The opposite is true in children, who need larger doses of propofol. This is particularly so in children under three years of age. Propofol is not recommended for induction of anaesthesia in children under one month of age or for maintenance of anaesthesia in children under three years old.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
      2.7
      Seconds
  • Question 14 - Regarding hypertensive crises, which of the following statements is CORRECT: ...

    Correct

    • Regarding hypertensive crises, which of the following statements is CORRECT:

      Your Answer: In a hypertensive emergency, blood pressure should be reduced by 20 - 25% within 2 hours.

      Explanation:

      A hypertensive emergency is defined as severe hypertension (blood pressure ≥ 180/110 mmHg) with acute damage to the target organs. Prompt treatment with intravenous antihypertensive therapy is generally required; over the first few minutes or within 2 hours, blood pressure should be reduced by 20 – 25%. Severe hypertension without acute target organ damage is defined as hypertensive urgency.; blood pressure should be reduced gradually over 24 – 48 hours with oral antihypertensive therapy. If blood pressure is reduced too quickly in the management of hypertensive crises, there is a risk of reduced organ perfusion leading to cerebral infarction, blindness, deterioration in renal function, and myocardial ischaemia.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      1.8
      Seconds
  • Question 15 - All of the following cause bronchodilation, EXCEPT for: ...

    Correct

    • All of the following cause bronchodilation, EXCEPT for:

      Your Answer: Stimulation of irritant receptors

      Explanation:

      Factors causing bronchodilation: Via beta2-adrenoceptorsSympathetic stimulation: Adrenaline (epinephrine)Beta2-adrenergic agonists e.g. salbutamolAnticholinergic and muscarinic antagonists e.g. ipratropium

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      2.1
      Seconds
  • Question 16 - What is the mechanism of action of captopril: ...

    Correct

    • What is the mechanism of action of captopril:

      Your Answer: Angiotensin-converting enzyme inhibitor

      Explanation:

      Captopril is an angiotensin-converting enzyme (ACE) inhibitor, which inhibits the conversion of angiotensin I to angiotensin II.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      12.5
      Seconds
  • Question 17 - Which of the following medications may lessen warfarin's anticoagulant effect: ...

    Incorrect

    • Which of the following medications may lessen warfarin's anticoagulant effect:

      Your Answer: Acute alcohol consumption

      Correct Answer: Phenytoin

      Explanation:

      Phenytoin will decrease the level or effect of warfarin by affecting hepatic/intestinal enzyme CYP3A4 metabolism.Metronidazole will increase the level or effect of warfarin by affecting hepatic enzyme CYP2C9/10 metabolism.NSAIDs, when given with Warfarin, increase anticoagulation.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      109.8
      Seconds
  • Question 18 - Glucagon is contraindicated in which of the following: ...

    Correct

    • Glucagon is contraindicated in which of the following:

      Your Answer: Pheochromocytoma

      Explanation:

      Glucagon is contraindicated in pheochromocytoma.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      47.2
      Seconds
  • Question 19 - In the ventricular myocyte action potential, depolarisation occurs through the opening of: ...

    Correct

    • In the ventricular myocyte action potential, depolarisation occurs through the opening of:

      Your Answer: Voltage-gated Na + channels

      Explanation:

      An action potential (AP) is initiated when the myocyte is depolarised to a threshold potential of about -65 mV, as a result of transmission from an adjacent myocyte via gap junctions. Fast voltage-gated Na+channels are activated and a Na+influx depolarises the membrane rapidly to about +30 mV. This initial depolarisation is similar to that in nerve and skeletal muscle, and assists the transmission to the next myocyte.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      35.4
      Seconds
  • Question 20 - The following all cause a left shift in the oxygen dissociation curve EXCEPT...

    Correct

    • The following all cause a left shift in the oxygen dissociation curve EXCEPT for:

      Your Answer: Decrease in pH

      Explanation:

      An increased affinity of haemoglobin for oxygen, shown by a left shift in the oxygen dissociation curve, is caused in the lungs by a rise in pH, a fall in PCO2,a decrease in temperature and a decrease in 2,3 -DPG. Carbon monoxide (CO) binds 240 times more strongly than O2to haemoglobin and by occupying O2-binding sites, reduces oxygen capacity. CO also increases oxygen affinity, shifting the oxygen haemoglobin curve to the left and making O2release to tissues more difficult.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      17.1
      Seconds
  • Question 21 - You've been summoned to a young man in the resus area who has...

    Incorrect

    • You've been summoned to a young man in the resus area who has an SVT. You decide to use adenosine after trying several vagal manoeuvres without success.The use of adenosine is not contraindicated in which of the following situations?

      Your Answer: 3 rd -degree AV block

      Correct Answer: Concurrent use of a beta-blocker

      Explanation:

      The use of a beta-blocker at the same time increases the risk of myocardial depression, but it is not a contraindication.The use of adenosine is contraindicated in the following situations:AsthmaCOPD (chronic obstructive pulmonary disease)Decompensated heart failure Long QT syndromeAV block in the second or third degreeSinusitis is a condition in which the sinuses become (unless pacemaker fitted)Hypotension that is severe

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      69.9
      Seconds
  • Question 22 - A patient presents with nausea, anorexia, jaundice and right upper quadrant pain. A...

    Correct

    • A patient presents with nausea, anorexia, jaundice and right upper quadrant pain. A diagnosis of acute hepatitis B is suspected.Which of the following blood results is most suggestive of an acute hepatitis B infection? Select ONE answer only.

      Your Answer: HBsAg positive, IgM anti-HBc positive

      Explanation:

      Hepatitis B surface antigen (HBsAg) is a protein on the surface of the hepatitis B virus, that is the first serologic marker to appear in a new acute infection.It can be detected as early as 1 week and as late as 9 weeks. It can be detected in high levels in serum during acute or chronic hepatitis B virus infection. The presence of HBsAg indicates that the person is infectious. The body normally produces antibodies to HBsAg as part of the normal immune response to infection. HBsAg is the antigen used to make hepatitis B vaccine.Hepatitis B surface antibody (anti-HBs) indicates recovery and immunity from the hepatitis B virus infection. Anti-HBs also develops in a person who has been successfully vaccinated against hepatitis B.Total hepatitis B core antibody (anti-HBc): Appears at the onset of symptoms in acute hepatitis B and persists for life. The presence of anti-HBc indicates previous or ongoing infection with hepatitis B virus in an undefined time frame. It is not present following hepatitis B vaccination.IgM antibody to hepatitis B core antigen (IgM anti-HBc) indicates recent infection with hepatitis B virus (<6 months). Its presence indicates acute infection.The following table summarises the presence of hepatitis B markers according to each situation:Susceptible to infection:HBsAg = NegativeAnti-HBc = NegativeAnti-HBs = NegativeImmune due to natural infection:HBsAg = NegativeAnti-HBc = PositiveAnti-HBs = PositiveImmune due to vaccination:HBsAg = NegativeAnti-HBc = NegativeAnti-HBs = PositiveAcute infection:HBsAg = PositiveAnti-HBc = PositiveAnti-HBs = NegativeIgM anti-HBc = PositiveChronic infection:HBsAg = PositiveAnti-HBc = PositiveAnti-HBs = NegativeIgM anti-HBc = Negative

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      33.9
      Seconds
  • Question 23 - Regarding antihistamines, which of the following statements is CORRECT: ...

    Correct

    • Regarding antihistamines, which of the following statements is CORRECT:

      Your Answer: Elderly patients and children are more susceptible to side effects.

      Explanation:

      Elderly patients and children are more susceptible to side effects. Antihistamines are competitive inhibitors at the H1-receptor. The newer antihistamines e.g. cetirizine cause less sedation and psychomotor impairment than the older antihistamines because they are much less lipid soluble and penetrate the blood brain barrier only to a slight extent. Antihistamines are used as a second line adjunct to adrenaline in anaphylaxis.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory
      15.7
      Seconds
  • Question 24 - On his stool culture, a patient with a diarrhoeal illness grows Escherichia coli.What...

    Incorrect

    • On his stool culture, a patient with a diarrhoeal illness grows Escherichia coli.What SINGLE statement about Escherichia coli is true?

      Your Answer: It is an obligate anaerobe

      Correct Answer: Most serotypes are harmless

      Explanation:

      Escherichia coli is a Gram-negative, non-spore forming, facultative anaerobic, rod-shaped bacterium. Although some can cause serious food poisoning, most serotypes are harmless.Escherichia coli is transmitted via the faeco-oral route.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      12.7
      Seconds
  • Question 25 - A patient presents to ED complaining of pins and needles over the lateral...

    Correct

    • A patient presents to ED complaining of pins and needles over the lateral three and a half digits. You suspect carpal tunnel syndrome. Which of the following clinical features would you most expect to see on examination:

      Your Answer: Inability to touch the pad of the little finger with the thumb

      Explanation:

      Compression of the median nerve in the carpal tunnel will result in weakness and atrophy of the thenar muscles – resulting in weakness of opposition, abduction and flexion of the thumb at the metacarpophalangeal joint and anaesthesia or paraesthesia over the distribution of the palmar digital branch of the median nerve (skin over the palmar surface and fingertips of the lateral three and a half digits). The adductor pollicis muscle is innervated by the ulnar nerve, and abduction of the fingers is produced by the interossei, also innervated by the ulnar nerve. Flexion of the interphalangeal joint of the thumb is produced by the flexor pollicis longus, and flexion of the distal interphalangeal joint of the index finger is produced by the flexor digitorum profundus. Median nerve injury at the wrist will not affect the long flexors of the forearm as these are innervated by the anterior interosseous nerve which arises in the proximal forearm.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      17.3
      Seconds
  • Question 26 - Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the...

    Incorrect

    • Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the following:

      Your Answer: Thyrotropin-releasing hormone

      Correct Answer: Corticotropin-releasing hormone

      Explanation:

      ACTH secretion is stimulated by corticotropin-releasing hormone (CRH) from the hypothalamus.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      9.8
      Seconds
  • Question 27 - Regarding the hard palate, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding the hard palate, which of the following statements is CORRECT:

      Your Answer: The anterior three-quarters of the hard palate is formed by the palatine bones.

      Correct Answer: Lymphatic vessels from the palate usually drain into deep cervical lymph nodes.

      Explanation:

      Lymphatic vessels from the pharynx and palate drain into the deep cervical lymph nodes.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      60.9
      Seconds
  • Question 28 - A 57-year-old woman receives vitamin B12 injections following a gastrectomy.Which of the following...

    Correct

    • A 57-year-old woman receives vitamin B12 injections following a gastrectomy.Which of the following cell types, if absent, is responsible for her vitamin B12 deficiency?

      Your Answer: Parietal cells

      Explanation:

      Intrinsic factor, produced by the parietal cells of the stomach, is essential for the absorption of vitamin B12 from the terminal ileum. After a gastrectomy, the absorption of vitamin B12 is markedly reduced, and a deficiency will occur.

    • This question is part of the following fields:

      • Gastrointestinal Physiology
      • Physiology
      12.3
      Seconds
  • Question 29 - A 28-year-old female patient with a history of hypothyroidism arrives at the Emergency...

    Incorrect

    • A 28-year-old female patient with a history of hypothyroidism arrives at the Emergency Department after taking 30 of her 200 mcg levothyroxine tablets. She tells you she's 'tired of life' and 'can't take it any longer.' She is currently asymptomatic, and her findings are all within normal limits.What is the minimum amount of levothyroxine that must be taken before thyrotoxicosis symptoms appear?

      Your Answer: >1 mg

      Correct Answer: >10 mg

      Explanation:

      An overdose of levothyroxine can happen by accident or on purpose. Intentional overdosing is sometimes done to lose weight, but it can also happen in patients who are suicidal. The development of thyrotoxicosis, which can lead to excited sympathetic activity and high metabolism syndrome, is the main source of concern. The time between ingestion and the emergence of clinical features associated with an overdose is often quite long.After a levothyroxine overdose, the majority of patients are asymptomatic. Symptoms and signs are usually only seen in patients who have taken more than 10 mg of levothyroxine in total.The following are the most commonly seen clinical features in patients developing clinical features:TremorAgitationSweatingInsomniaHeadacheIncreased body temperatureIncreased blood pressureDiarrhoea and vomitingLess common clinical features associated with levothyroxine overdose include:SeizuresAcute psychosisThyroid stormTachycardiaArrhythmiasComaThe continued absorption of the ingested levothyroxine causes a progressive rise in both total serum T4 and total serum T3 levels in the first 24 hours after an overdose. However, in some cases, the biochemical picture is completely normal. Thyroid function tests are not always recommended after a thyroxine overdose. Although elevated thyroxine levels are common, they have little clinical significance and have no impact on treatment. Following a levothyroxine overdose, the following biochemical features are common:T4 and T3 levels in the blood are elevated.Free T4 and Free T3 levels are higher.TSH levels in the blood are low.If the patient is cooperative and more than 10 mg of levothyroxine has been consumed, activated charcoal can be given (i.e., likely to become symptomatic)Within an hour of ingestion, the patient presents.The treatment is mostly supportive and aimed at managing the sympathomimetic symptoms that come with levothyroxine overdose. If beta blockers aren’t an option, try propranolol 10-40 mg PO 6 hours or diltiazem 60-180 mg 8 hours.

    • This question is part of the following fields:

      • Endocrine Pharmacology
      • Pharmacology
      88.6
      Seconds
  • Question 30 - Regarding the glomerular filtration barrier, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding the glomerular filtration barrier, which of the following statements is CORRECT:

      Your Answer: Negatively charged molecules are filtered more freely than positively charged ones.

      Correct Answer: The main factor determining whether a substance is filtered or not is molecular weight.

      Explanation:

      Molecular weight is the main factor in determining whether a substance is filtered or not – molecules < 7 kDa in molecular weight are filtered freely e.g. glucose, amino acids, urea, ions but larger molecules are increasingly restricted up to 70 kDa, above which filtration is insignificant. Negatively charged molecules are further restricted, as they are repelled by negative charges, particularly in the basement membrane. Albumin has a molecular weight of 69 kDa and is negatively charged, thus only very small amounts are filtered (and all of the filtered albumin is reabsorbed in the proximal tubule), whereas small molecules such as ions, glucose, amino acids and urea pass the filter without hindrance. This means that ultrafiltrate is virtually protein free, but otherwise has an identical composition of that of plasma. The epithelial lining of the Bowman's capsule consists of a single layer of cells called podocytes. The glomerular capillary endothelium is perforated by pores (fenestrations) which allow plasma components with a molecular weight of < 70 kDa to pass freely.

    • This question is part of the following fields:

      • Physiology
      • Renal
      33.7
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Anaesthesia (2/2) 100%
Pharmacology (9/12) 75%
Basic Cellular Physiology (1/1) 100%
Physiology (10/12) 83%
Anatomy (3/4) 75%
Upper Limb (2/2) 100%
Cardiovascular (4/5) 80%
Central Nervous System (2/2) 100%
Gastrointestinal (1/1) 100%
Endocrine (2/3) 67%
Respiratory (4/4) 100%
Gastrointestinal Physiology (2/2) 100%
Cardiovascular Pharmacology (1/2) 50%
Renal (1/2) 50%
Microbiology (1/2) 50%
Specific Pathogen Groups (1/2) 50%
Head And Neck (0/1) 0%
Endocrine Pharmacology (0/1) 0%
Passmed