Pharmacology Flashcards
Which local anaesthetic agent is an amide?
Lidocaine
The other local anaesthetic agents are esters (procaine)
With regard to the neuromuscular junction, what causes a reduction in the release of acetylcholine?
Aminoglycoside
Which agent is a neurotransmitter used by the sympathetic preganglionic neuron?
acetylcholine. Both the parasympathetic and sympathetic preganglionic neurons use acetylcholine as a neurotransmitter.
Methyldopa MOA:
selective alpha 2 agonist
Phenylephrine MOA:
alpha 1 agonist
Amlodipine MOA
Calcium antagonist
What are the vitamin K-dependent clotting factors?
10 9 7 2
Warfarin’s full effect is delayed for 3 days and has a half life of 40 hours.
cyclizine MOA
H1 antagonist
ranitidine MOA
H2 antagonists
A patient has developed a deep vein thrombosis postoperatively and is treated with warfarin.
What is the targeted international normalised ratio (INR) range for this patient?
2-3
What is the most appropriate treatment for pelvic inflammatory disease?
Ceftriaxone 250 mg and azithromycin 1 g for 7 days
A 23-year-old woman is newly diagnosed with thyrotoxicosis. She is 20 weeks pregnant.
Which medication will be the most appropriate treatment?
Propylthiouracil
- Carbimazole and PTU are the most commonly used antithyroid drugs in the UK.
- There is no need to change carbimazole dosage if the woman is already well maintained on it. However PTU is the drug of choice for all newly diagnosed cases
Obese dose of Enoxaparin
60mg
Normal dose of Enoxparain
40mg
An anomaly scan done at 20 weeks’ gestation reveals the presence of depressed nasal bridge, stippling of non-calcified epiphyses and microcephaly. What drug?
Warfarin
In women with a prosthetic heart valve replacement, there is are an undisputed indication for warfarin usage.
Sodium valproate fetal effects:
depressed nasal bridge
neural tube defects, cardiac defects
What is the main reason for taking vitamin D during pregnancy?
To prevent rickets in the neonate
Pre-pregnancy BMI is inversely associated with serum vitamin D concentrations, and obese pregnant women are at increased risk.
You have been asked to prescribe a combined oral contraceptive pill to a woman with acne and hirsutism. She is known to have polycystic ovary syndrome (PCOS).
What is the best available option?
Yasmin (ethinylestradiol / drosperinone)
Best PCOS option for contraception (rather than acne/hisutism)?
Marvelon (ethinylestradiol, desogestrel)
Mercilon (ethinylestradiol, desogestrel)
Mirena (levonorgestrel) is a good option for contraception in women with PCOS because it provides protection to the endometrium (by opposing the unopposed estrogen in PCOS).
Which medication may be used to reduce the symptom of stress incontinence?
duloxetine
Duloxetine is a balanced serotonin and noradrenaline reuptake inhibitor.
Which medication may be used to reduce the symptom of urge incontinence?
Tolterodine and oxybutynin are muscarinic receptor antagonists and are used in urge incontinence.
How can the mechanism of action of ranitidine best be described?
It reduces the acid content and production by gastric parietal cells
Ciprofloxacin is a quinolone antibiotic.
What is its mode of action?
Inhibits DNA gyrase
Which drug prevents the peripheral deiodination of thyroxine?
propylthiouracil.
Which chemotherapy agent inhibits dihydrofolate reductase?
Methotrexate
Fluorouracil MOA:
inhibits thymidylate synthase.
Tranexamic acid is often prescribed to treat heavy menstrual bleeding.
What is the mode of action of this drug?
Inhibits plasmin formation
Which e drugs undergo cytochrome p450-dependent hydroxylation?
Warfarin
phenobarbital, propranolol, phenytoin
A 22-year-old woman is discharged from the postnatal ward following a normal birth. She wishes to discuss contraception options as this pregnancy was unplanned. She is breastfeeding and has a history of pelvic inflammatory disease.
What is the most appropriate contraceptive method in her case?
POP
- IUCD is contraindicated because of the history of pelvic inflammatory disease.
- Combined oral contraceptive pills are not the contraceptives of choice in breastfeeding mothers because of their potential effect on the volume of breast milk.
Alpha methyl dopa is a commonly used antihypertensive in pregnancy, when is it contraindicated?
Is relatively contraindicated in the puerperal period due to risk of postnatal depression.
Maternal use of metronidazole whilst breastfeeding is associated with the infant having?
Diarrhoea
What is the concern of Nitrofurantoin being excreted into breastmilk?
can cause haemolysis in G6PD deficient infants (a rare condition)
A woman in her first pregnancy develops hypertension and proteinuria at 39 weeks of gestation, so labour is induced. The birth is assisted by ventouse and with the delivery of the baby’s anterior shoulder, the midwife administers an oxytocic agent for active management of the third stage of labour.
What drug is the most appropriate in this case?
Syntocinon
Syntometrine avoided due to increased BP.
A woman is taking rivaroxaban because she sustained a deep vein thrombosis following an operation 2 months ago. Having stopped taking her contraceptive pill peri-operatively, she now finds that she is unexpectedly 8 weeks pregnant.
If she wishes to continue with the pregnancy, what should be done about her anticoagulation?
Change to low molecular weight heparin
Women with previous VTE (except those with a single previous VTE related to major surgery and no other risk factors) should be offered thromboprophylaxis with LMWH throughout the antenatal period.
MOA of NOACs:
Non-vitamin K antagonist oral anticoagulants (NOACs, previously known as new/novel oral anticoagulants) such as dabigatran, rivaroxaban and apixaban work through direct inhibition of thrombin or factor Xa. They are not licensed for use in pregnancy where there is no experience in their use. Aspirin is not adequate.
How long after a dose of low molecular weight heparin can an epidural catheter be removed?
12 hours
Which antiepileptic medication is associated with autism in the child if taken in pregnancy?
Sodium valproate
Which risk factors for pre-eclampsia should cause someone to take aspirin?
previous hypertensive disease in pregnancy
chronic kidney disease
autoimmune disease such as SLE, antiphospholipid syndrome, diabetes mellitus
chronic hypertension
or two moderate risk factors (first pregnancy, age 40 or over, pregnancy interval > 10 years, BMI>35, family history, multiple pregnancy
What is the dose of prophylactic aspirin for pre-eclampsia?
75-150 mg aspirin daily from 12 weeks of gestation until term.
Which antihypertensive should be avoided in pregnancy?
Ramipril
ACEs and ARBs (Candesartan)
What are the problems with NSAIDs in pregnancy?
neonatal pulmonary hypertension and premature closure of the ductus arteriosus.
reduce fetal renal blood flow leading to oligohydramnios.
Which anti-emetic has extrapyramidal side effects?
Metoclopramide
Metoclopramide is used as a second-line therapy because of the risks of extrapyramidal side effects and tardive dyskinesia
mechanism of action of LMWH?
Inhibits factor Xa by binding to anti-thrombin, thereby inhibiting the conversion of prothrombin to thrombin
Which compounds can be found as the estrogen component in combined oral contraception formulations?
Ethinylestradiol
Mestranol
Estradiol valerate
Conjugated equine estrogen is used in HRT preparations
What is the side effect most commonly seen in a newborn exposed to labetalol?
Hypotension
A 40-year-old woman with heavy menstrual periods is having carboxymaltose (Ferinject™) treatment for the last 6 months whilst she awaits a hysterectomy procedure, because she cannot tolerate oral iron.
What is the electrolyte disturbance associated with long-term use of ferric carboxymaltose?
Hypophosphatemia
