GI & Surgery Flashcards

Question

what other drugs can be used in treatment of IBS

Answer 1

mebeverine hyoscine butylbromide (buscopan) peppermint oil

Answer 2

Aminosalicylates – mesalazine, olsalazine, sulfasalazine Corticosteroids – hydrocortisone, prednisolone, budesonide Cytokine Modulators – adalimumab, infliximab(Anti-TNFα antibodies) Antimetabolites – azathioprine, methotrexate Antibiotics – metronidazole

Answer 3

systemic infections gastritis diabetes HF osteoporosis growth suppression in children

Answer 4

mesalazine suppository mesalazine enema budesonide enema oral 5ASA max dose

Answer 5

max oral 5 ASA + topical therapy + oral steroids Pred

Answer 6

allopurinol febuxostat slow elimination of 6MP

Answer 7

Infliximab is a chimeric monoclonal which has a high specificity for and affinity to tumor necrosis factor (TNF)-alpha. Infliximab neutralizes the biologic activity of TNF-alpha by inhibiting binding to its receptors. Infliximab can also stimulate apoptosis of activated lymphocytes in the gut mucosa

Answer 8

Adalimumab is a recombinant fully human monoclonal antibody that binds to TNF-alpha, thereby interfering with binding to TNF-alpha receptor sites and subsequent cytokine-driven inflammatory processes.

Answer 9

SE bacterial resistance eradication of normal flora (ABA colitis and increased risk of C.diff) cost-effectiveness

Answer 10

oral vancomycin fidoxamin IV metronidazole

Answer 11

GI = diarrhoea, N+V BM = myelosupression, --> anaemia, neutropenia and thrombocytopenia Alopecia infertility tumour lysis syndrome = Rapid breakdown of malignant cells can cause hyperuricaemia, hyperkalaemia, hyperphosphatemia, hypocalcaemia (due to the former) with consequent renal damage / arrhythmias.

Answer 12

- anti-metabolites is a pro-drug of fluorouracil interferes with DNA synthesis stops cells from making + repairing DNA (pyrimidine antagonist)

Answer 13

oral twice a day for 14 days

Answer 14

platinum based chemo drug MOA - causes DNA crosslinking which inhibits replication and transcription --> inhibition of DNA synthesis --> apoptosis (binds to guanine) induces both interstrand and intrastrand cross links unlike cisplatin often used in CRC cancer alongside fluorouracil and leucovorin gastroesophageal pancreatic

Answer 15

N+V, nephrotoxic, ototoxic, peripheral neuropathy and myelosuppression Neuropathy (Peripheral Neuropathy) – cold-induced paresthesia, chronic sensory neuropathy Nausea and vomiting Myelosuppression – neutropenia, thrombocytopenia, anemia Diarrhea Fatigue Hypersensitivity reactions – can cause anaphylaxis in some cases Hepatotoxicity – sinusoidal obstruction syndrome Acute laryngopharyngeal dysesthesia – sensation of throat tightness when exposed to cold

Answer 16

oxiplatinin cisplatin carboplatin used for solid malignancy cisplatin and carboplatin for ovarian and lung tumours SCLC + NSCLC

Answer 17

class = aromatase inhibitor inhibits aromatase enzyme which converts androgens into oestrogens. so decreased oestrogen deprives tumour of it however due to lower levels of oestrogen the SE are like menopause and osteoporosis

Answer 18

Severe skin reaction, mucous membranes frequently involved Blisters, fever, flu-like symptoms If left untreated can progress to sepsis, multi-organ failure and death

Answer 19

selective estrogen receptor modulator (SERM) Acts as an estrogen receptor antagonist in breast tissue, blocking estrogen's ability to promote cancer growth. Acts as an estrogen receptor agonist in other tissues, such as the bone, uterus, and liver, which contributes to some of its side effects. regimen = 20mg once a day for 5 years side effects = menopausal, VTE and stroke (so contraindicated in Fhx of vte or genetic predisposition)

Answer 20

SSRIs thought to reduce action of tamoxifen warfarin: tamoxifen inhibits CYP3A4 so increases risk of bleeding

Answer 21

Induction (of remission) – intensive IV treatment including intrathecal treatment, aimed at destroying as many leukaemia cells as possible and achieving remission (no leukaemia cells on bone marrow biopsy). Lasts 4-6 weeks, 3-4 agents (see next slide). Consolidation (of remission) – 3-4 months- aimed at remission and preventing spread. Often involves intrathecal injections (methotrexate) and then tablets. Maintenance (of remission) – lasts 1-3 years. Involves regular tablets and possible injections. Often 6-MP and weekly PO methotrexate

Answer 22

cyclophosphamide vincristine doxorubicin dexamethasone

Answer 23

Combinations of chemotherapy drugs are often used as this exploits multiple mechanisms of action and efficacy at different stages of the cell cycle. Combination treatments can result in enhanced response and reduced development of drug resistance.

Answer 24

- alkylating agent used in breast cancer, lymphomas, leukemias, and sarcomas. Alkylates DNA, forming covalent bonds with DNA bases, leading to DNA cross-linking. --> inhibits rep and trasncription --> apoptosis

Answer 25

Bone marrow suppression and neutropenia Can develop other malignancies e.g.: Acute Myeloid leukaemia, Bladder cancer (risk reduced by giving Mesna (mercaptoethane sulphonic acid) prior to treatment) Haemorrhagic cystitis Impaired fertility lifelong Hair loss, GI upset (pre-medication with anti-emetic)

Answer 26

Member of the Vinca Alkaloids Miotic inhibitors Binds to tubulin molecules and prevent the formation of microtubules, preventing chromosome separation Leads to cell death Sensory and motor neuropathies are common and cumulative.

Answer 27

- is a cytotoxic antibiotic (anthracycline) Inhibits topoisomerase II, an enzyme that unwinds DNA during replication. This results in the accumulation of DNA breaks.

Answer 28

dilated cardiomyopathy myelosuppression NV alopecia red urine

Answer 29

Folic acid antagonist Antimetabolite DMARD used in rheumatoid arthritis, psoriasis etc Other uses include molar or ectopic pregnancy Renal excretion Hepatotoxic/cirrhosis, pneumonitis, photosensitivity and ulceration (plus usual myelosuppression, GI toxicity of other chemotherapies)

Answer 30

Hyperalgesia is an increased sensitivity to painful stimuli, while allodynia is the perception of pain from non-noxious stimuli, often resulting from tissue trauma and the release of inflammatory mediators.

Answer 31

Pain impulses are transmitted to the dorsal horn of the spinal cord, where they contact second-order neurons that cross to the opposite side and ascend via the spinothalamic tract to the reticular activating system (RAS) and thalamus.

Answer 32

The transmission of nociceptive impulses is modulated by dorsal horn circuitry that receives input from peripheral touch and nociceptors, as well as from descending pathways involving the limbic cortical systems and other brain regions.

Answer 33

constipation, urinary retention, nausea, pruritis/urticaria, sedation, and respiratory depression.

Answer 34

Less common side effects of opioids include delirium, confusion, myoclonus/muscle rigidity, hallucinations, hyperalgesia, flushing/sweating, dry mouth, sexual dysfunction, hypotension, biliary/ureteric spasm, difficulty with micturition, and visual disturbance.

Answer 35

A competitive antagonist, like naloxone, reduces the potency of an agonist by competing for the same binding site, but high concentrations of the agonist can still produce a maximal response.

Answer 36

A shorter half-life means that naloxone may need to be administered multiple times or monitored closely, as its effects may wear off before the effects of the opioid have fully dissipated.

Answer 37

The limbic system, including structures like the orbital frontal cortex and amygdala, provides emotional context to pain perception and can modulate the experience of pain.

Answer 38

Multimodal analgesia is an approach to pain management that utilizes a combination of different medications and techniques to control pain effectively, targeting various pain pathways to enhance analgesic effects and reduce the need for opioids.

Answer 39

strong short acting opioid - buccal fentanyl?

Answer 40

ondansetron is a 5HT3 receptor antagonist at both peripheral and chemoreceptor trigger zone

Answer 41

1) dexamethasone as preventative 2) anticholinergics like scopolamine as a preventative patch 3) neurokinin receptor antagonists like aprepitant as preventative. * is expensive 4) metoclopramide D2 antagonist

Answer 42

1) extrapyramidal effects like acute dystonia (oculogyric crisis) 2) diarrhoea 3) hyperprolactinemia 4) tardive dyskinesia 5) parkinsonism

Answer 43

procyclidine

Answer 44

- ondansetron = gold standard - Anti-histamines like promethazine - anti-cholinergics like scopolamine if N persistent - D2 antagonists like metoclopramide Non-Pharmacological Approaches Dose adjustment or switching opioids (e.g., morphine to fentanyl) to reduce nausea. Hydration and electrolyte balance – IV fluids if vomiting is severe. Ginger or acupressure – complementary therapy.

Answer 45

1) hyoscine butylbromide 2) anti-histamines like cinnarazine and cyclizine more sedating = promethazine Avoid reading and focus on the horizon. Sit in the front seat of a car or near the wings of a plane. Fresh air and hydration. Acupressure wristbands (P6 stimulation).

Answer 46

1) ondansetron 2) metoclopramide 3) dexamethasone 4) scopolamine 5) aprepitant

Answer 47

in acute phase use ondansetron after or dexa/aprepitant before chemo in delayed phase also use aprepitant and dexa Non-Pharmacological Approaches Dietary modification – small, bland meals. Psychological techniques – guided imagery, relaxation therapy. Ginger, acupuncture – adjunct therapies.

Answer 48

non pharm: - rest, oral hydration and dietary changes - ginger - chlorpromazine - cyclizine -doxylamine with pyridoxine - metoclopramide - ondansetron

Answer 49

0.9% sodium chloride and compound sodium lactate (Hartmann’s solution). 5% glucose (initially isotonic but becomes hypotonic)

Answer 50

Hypertonic glucose solutions are those with higher concentrations of glucose, such as 10% glucose, 20% glucose, and 50% glucose.

Answer 51

The NICE guideline recommends using 0.9% sodium chloride, compound sodium lactate (Hartmann’s), and 5% glucose, with or without KCl.

Answer 52

Balanced crystalloid (first-line): Plasma-Lyte 148 or Hartmann’s solution (Ringer’s lactate) Alternatives (if no balanced crystalloids available): 0.18% NaCl + 4% glucose + 27 mmol/L KCl at 25–30 mL/kg/day 5% dextrose with KCl if sodium levels are normal Typically 1,000 mL over 8–12 hours, adjusted based on patient condition.

Answer 53

in hypovolemia/shock First-line fluid: Balanced crystalloid (Hartmann’s or Plasma-Lyte 148) at 500 mL IV over 15 minutes. Repeat up to 2 L if needed (reassess after each bolus). 0.9% Normal Saline (NS) if no balanced crystalloids are available.

Answer 54

Step 1: Identify & Correct the Cause Common causes: Diuretics (loop/thiazides), diarrhea, vomiting, alkalosis, insulin therapy, magnesium deficiency. Step 2: Choose the Correct IV Potassium Replacement Mild (K⁺ 3.0–3.5 mmol/L, asymptomatic): Oral KCl 40–80 mmol/day (preferred if patient can tolerate oral intake). Moderate (K⁺ 2.5–3.0 mmol/L, symptoms present): IV KCl 20–40 mmol in 1,000 mL of 0.9% NaCl over 4–6 hours. Severe (K⁺ <2.5 mmol/L, ECG changes, severe symptoms): IV KCl 20 mmol in 100 mL 0.9% NaCl over 1 hour (via central line if rapid correction is needed). Maximum rate: Peripheral IV: 10 mmol/hr. Central line: 20 mmol/hr (requires cardiac monitoring). Check Mg²⁺ levels – replace if low (Mg²⁺ is necessary for K⁺ retention).