Pharmacology Flashcards
(177 cards)
1
Q
What do strong opioids act as?
A
Mu receptors agonists
2
Q
What do weak opioids act as?
A
Mu, delta or kappa receptor agonists
3
Q
What are the features of warfarin embryopathy?
A
Hypoplasia of nasal bridge Congenital heart defects Ventriculomegaly Agenesis of the corpus callosum Stippled epiphyses
4
Q
What proportion of exposed fetuses develop warfarin embryopathy?
A
5%
5
Q
At what gestation may warfarin embryopathy occur?
A
6-12 weeks
6
Q
How does warfarin work?
A
Inhibits vitamin K dependent clotting factors - 10,9,7,2
7
Q
Is warfarin safe to use in breastfeeding?
A
Yes
8
Q
What should warfarin be switched for during pregnancy?
A
LMWH
9
Q
What are the 2 most common dihydrofolate reductase (DHFR) inhibitors?
A
1) Methotrexate
2) Trimethoprim
10
Q
What is the max dose of lidocaine?
A
3mg/kg (7mg/kg with adrenaline)
11
Q
What is the lidocaine conversion?
A
1% lidocaine =1g/100mL or 10mg/mL
12
Q
What is the half-life of lidocaine?
A
2 hours
13
Q
What is the mechanism of action of lidocaine?
A
Blocks fast voltage gated sodium channels
14
Q
What are the 2 different antenatal steroid courses available?
A
Betamethasone 12 mg IM x 2 doses or
Dexamethasone 6 mg IM x 4 doses
15
Q
How many x more potent is fentanyl than morphine?
A
x80-100
16
Q
What are the adverse effects of ACEi/ARBs on a fetus?
A
1) Congenital Malformations
2) Renal dysgenesis
3) Oligohydramnios as a result of fetal oliguria
4) Pulmonary hypoplasia
5) IUGR
6) Neonatal anuric renal failure
17
Q
What are the adverse effects of carbimazole on a fetus?
A
1) Choanal atresia
2) GIT defects
3) Omphalocoele
4) Aplasia cutis
18
Q
What is the mode of action of cyclizine?
A
Histamine H1-receptor antagonist
19
Q
What is the mode of action of promethazine?
A
Histamine H1-receptor antagonist
20
Q
What is the mode of action of ondansetron?
A
Serotonin 5-HT3 receptor antagonist
21
Q
What is the mode of action of prochlorperazine?
A
Dopamine D2 receptor antagonist
22
Q
What is the mode of action of metoclopramide?
A
Dopamine D2 receptor antagonist
5-HT3 receptor antagonist
5-HT4 receptor agonist
23
Q
In whom would you not consider metoclopramide in pregnancy and why?
A
In those <20 years old due to the risk of oculogyric crisis
24
Q
When may warfarin be restarted after delivery?
A
5-7 days after - although it is safe in breastfeeding the delay is due to to the risk of PPH
25
What are the phase 1 reactions of drug metabolism?
Oxidation, reduction or hydrolysis ---> leading to products being more reactive
26
What are the phase 2 reactions of drug metabolism?
Conjugation ---> leading to inactivation of a drug
27
In those at risk of VTE, when should LMWH be started?
In the first trimester
28
How does heparin prevent coagulation?
Inactivation of antithrombin III
29
What are the S/Es of heparin?
1) Bleeding
2) Thombocytopenia
3) Hypoaldosteronism
4) Osteoporosis
30
What is the most common inherited haemostatic disorder?
Von Willebrand's
31
What blood test profile represents Von Willebrand's
PT = unaffected
APTT = prolonged
Bleeding time = prolonged
Plt count = unaffected
32
Which Abx damage the 8th cranial nerve in the fetus and are ototoxic?
The aminoglycosides - e.g. gentamicin and streptomicin
33
Which Abx can cause neonatal haemolysis?
Both sulphonamides and trimethoprim (an co-trimoxazole which is a combination of the two)
34
Which local anaesthetic(s) are amide?
Lidocaine
35
Which local anaesthetic(s) are ester?
Benzocaine; procaine; tetracaine
36
Which anti-hypertensive is an alpha-2-agonist?
Methyldopa
37
What is the half life of warfarin?
40 hours
38
How long does it take for warfarin to reach its full effect?
3 days
39
How does tranexamic acid work?
Inhibits the activation of plasminogen
40
Maternal use of metronidazole during breastfeeding is associated with what in the infant?
Diarrhoea
41
Over what period after administration are corticosteroids most effective in reducing respiratory distress if delivery occurs?
24 hours - 7 days
42
Through which mechanism of action and which receptor does cabergonline suppress lactation?
Agonist at D2 receptor
43
What is the mechanism of action of clomifene?
Blocks oestrogen receptors in the hypothalamus, increasing FSH pulse frequency
44
What is the mechanism of action of mifepristone?
Progesterone antagonist
45
What type of drug is misoprostal?
Synthetic prostaglandin
46
What is the main estrogenic component of the combined oral contraceptive pill?
Ethinylestradiol
47
What class of drug is ulipristal acetate?
Selective progesterone receptor modulator
48
What is the mechanism of action of hydralazine?
Direct smooth muscle relaxant
49
Which enzyme is blocked by acetazolamide?
Carbonic anhydrase
50
What is the total extra iron requirement in pregnancy?
1000mg
51
What is the major constituent of pulmonary surfactant?
Dipalmitoylphosphatidylcholine
52
What are the S/Es of labetolol?
IUGR, with prolonged use
53
What are the S/Es of methyldopa?
1) Rebound HTN
2) Depressed mood
3) Flattened CTG variability
4) Hepatitis
54
What type of drug is nifedipine?
Dihydropyridine - it blocks inwards flux of calcium through voltage gated channels
55
What are the S/Es of nifedipine?
1) Acute hypotension
2) Peripheral oedema
3) Headache and flushing
56
What are the affects of ACEi's in pregnancy?
1) Congential malformations, esp. to CVS
2) Skull defect
3) Oligohydramnios
57
What is the first line tocolytic?
Nifedipine
58
What is the 2nd line tocolytic?
Atosiban
59
What type of drug is atosiban?
Oxytocin antagonist
60
What drug may be given prior to ECV?
Terbutaline can increase procedural success in primips. It is a one-off dose and can cause S/Es of transient maternal tachycardia and tremor
61
Women at risk of pre-eclampsia and should be offered aspirin 75mg are:
1. HTN disease during pregnancy
2. CKD
3. Autoimmune disease e.g. SLE
4. T1DM or T2DM
5. Chronic HTN
62
What are the S/E of nitrous oxide?
Nausea
63
What are the S/Es of IM pethidine?
N+V
Narcosis
Respiratory depression in the neonate if given within 2 hours of delivery
64
In whom should carboprost be avoided?
Caution in HTN, avoided in asthma
65
In whom should ergometrine be avoided?
HTN
66
What are the potential side effects of epidural?
1) Hypotension
2) Loss of mobility
3) Higher chance of assisted delivery
4) Complications associated with insertion, e.g. dural tap, haematoma, high blockade
67
What may be used as an anti-emetic in resistant cases of HG where everything else have been tried?
Corticosteroids
68
Why is heartburn more common in pregnancy?
The action of progesterone on the lower oesophageal sphincter causes it to have reduced tone.
69
What is the mechanism of action of mefenamic acid?
Prostaglandin production inhibitor
70
By how much may mefenamic acid reduce bleeding?
30%
71
What is the mechanism of action of tranexamic acid?
Anti-fibrinolytic - blocks conversion of plasminogen to plasmin, reducing fibrinolysis
72
By how much may tranexamic acid reduced blood loss?
40-50%
73
What drugs may be used to reduce detrusor over-activity (urge incontinence)?
Tolterodine and oxybutynin - both are muscarinic antagonists on M3
74
What drug might be used in stress incontinence?
Duloxetine - it increases urinary sphincter tone, SNRI action
75
What are the different classes of cytotoxic agents?
1) Antimetabolites
2) Alkylating agents
3) Intercalating agents
4) Anti-tumour antibiotics
5) Drugs directed against spindle microtubules, inhibiting mitosis
76
What are examples of antimetabolites?
5-FU, methotrexate
77
What is an example of alkylating agents?
Cyclophosphamide
78
What are examples of intercalating agents?
Cisplatin, carboplatin
79
What are examples of anti-tumour antibiotics?
Bleomycin, doxorubicin
80
What are examples of drugs directed against spindle microtubules, inhibiting mitosis?
Vincristine
81
What is the mechanism of action of antimetabolites?
Interfere with DNA and RNA synthesis
82
What is the mechanism of action of alkylating agents?
Form covalent bonds in DNA
83
What is the mechanism of action of intercalating agents?
Bind to DNA and so inhibit replication
84
What is the mechanism of action of anti-tumour antibiotics?
Lead to inhibition of DNA synthesis
85
What are the side effects of chemo?
1. Bone marrow suppression - cellular nadir tends to occur at approx. 7-14 days
2. N&V
3. Mucositis - ulcers to mucous membranes, particularly oral, esp. with methotrexate
4. Diarrhoea - usually transient
5. Alopecia
6. Tinnitus - associated with cisplatin
7. Peripheral neuropathy
8. Lethargy
9. Anorexia
86
What chemo regimes are used in ovarian cancer?
Platinum-based regimes - carboplatin +/- paclitaxel
87
What chemo regimes are used in endometrial cancer?
More limited role, usually reserved for metastatic disease
| Caroplatin +/- paclitaxel, or doxorubicin and cisplatin
88
What chemo regimes are used in cervical cancer?
Cisplatin + radiotherapy
89
What chemo regime is used in vulval cancer?
%-FU +/- cisplatin in combination with radiotherapy for those unfit for surgery/symptoms control in metastatic disease
90
What is the most potent oestrogen in the reproductive years?
Estradiol, followed by estrone
91
What is the most potent oestrogen in the menopause?
Estrone
92
What are the two types of oestrogen receptor?
Alpha and beta
93
Where are alpha oestrogen receptors found?
Endometrium; bone; breast cancer cells; ovarian stroma cells; hypothalamus
94
Where are beta oestrogen receptors found?
Kidney; brain; bone; heart; lungs; intestinal mucosa; prostate; endothelial cells
95
Which receptor is the chief mediator of oestrogen on bone?
Alpha
96
How is oestrogen metabolised?
Primarily in the liver, by conjugation and hydroxylation
Conjugation = catalysed by glucuronyl transferases and sulphontransferases
Hydroxylation = catalysed by cytochrome P450
97
What will suppress hepatic SHBG production?
```
Androgens
Insulin
Corticoids
Progestogens
GH
```
98
What type of drug is clomifene?
Selective oestrogen receptor modulator
99
What is an alternative to NSAIDs/progesterone's/COCP/anti-fibrinolytic in reducing menstrual blood loss?
Danazol - isoxazole derivative of ethinyl testosterone - however androgen-like effects tend to be unacceptable to pts.
100
What is tibolone?
A synthetic steroid that has estrogenic, progestogenic and androgenic properties - it causes endometrial atrophy and so no withdrawal bleed, therefore an alternative to combined continuous HRT, can relieve menopausal symptoms and prevent bone loss
101
What is meant by bioavailability?
The proportion of drug that reaches the circulation unchanged - IV drugs therefore have 100% bioavailability
102
What is meant by volume of distribution?
Theoretical volume of water in which the amount of drug would need to be uniformly distributed to produce an observed blood concentration
103
What molecular weight must a drug be in order to be excreted by bile (and into faeces)?
>/= 300 Da
104
What are the effects of enzyme inducers?
Result in increased activity of cytochrome p450 enzyme, and therefore lower levels of the drug
105
What are some examples of enzyme inducers?
'CRAPS'
```
Carbemazepine
Rifampicin
A - bArbiturates
Phenytoin
St John's Wort
```
106
What are the effects of enzyme inhibitors?
Inhibit hepatic metabolisms resulting in increased plasma levels of the drug, increasing the risk of toxicity and side effects
107
What are some examples of enzyme inhibitors?
```
'Some Certain Silly Compounds Annoyingly Inhibit Enzymes, Grrrr'
Sodium valproate
Cimetidine
Sulphonamides
Ciprofloxacin
Antifungals/amiodarone
Isoniazid
Erythromycin/clary
Grapefruit juice
```
108
Which drugs do not cross the placenta?
Insulin
| Heparin - LMWH or unfractionated
109
When would a drug insult occur to cause limb reduction defects?
12-40 days
110
When would a drug insult occur to cause anencephaly?
24 days
111
When would a drug insult occur to cause transposition of the great vessels?
34 days
112
When would a drug insult occur to cause cleft lip?
36 days
113
When would a drug insult occur to cause VSD, syndactyly?
42 days
114
When would a drug insult occur to cause hypospadias?
84 days
115
Which drugs are teratogenic?
```
'All the A's'
1. AEDs
2, Abx
3. Anticoagulants
4. Antimetabolites
5. Antipsychotics
6. Acne drugs
7. Androgens
8. Alcohol
```
116
Which drugs are contraindicated in breastfeeding?
```
COCP - reduced milk
Theophylline - irritability
Aspirin - Reyes syndrome
Sedatives
Lithium
Amiodarone
Certain Abx - e.g. chloramphenicol can cause grey baby syndrome
Cytotoxics
```
117
Which AED can cause hirsutism?
Phenytoin
118
What is the mechanism of action of cabergoline?
Dopamine receptor D2 agonist
119
What is phase 4 of the human drug trials?
Post-marketing surveillance
120
What are the drugs that can cause abortion - using acronym MET?
M - misoprostal
E - ergotamine
T - thrombolytics
121
When does neonatal narcotics abstinence syndrome usually present?
Within 48 hours of delivery
122
Why may neonatal narcotics abstinence syndrome present beyond 48 hours after delivery?
It may occur up to 4/52 after delivery because methadone can be stored in the neonatal liver, lung and spleen
123
What are the fetal affects of cocaine?
1. FGR
2. Fetal death
3. Placental abruption
124
What are the features of fetal alcohol syndrome?
Growth - LBW
Craniofacial abnormalities - flat philtrum
CNS abnormalities - microcephaly, agenesis of the corpus callosum, cerebellar hypoplasia
Neurodevelopmental - epilepsy, hearing loss, cognitive deficit
125
What are the different groups of penicillins?
1. Beta-lactams
2. Beta-lactamase resistant
3. Broad-spectrum penicillins
4. Antipseudomonal penicillins
5. Mecillinams
126
What type of drug is oseltamivir?
Neuraminidase inhibitor
127
What are the side effects of HAART?
1. Lactic acidosis
2. Hyperglycaemia
3. Hepatitis
4. Pancreatitis
5. Peripheral neuropathy
128
What is the HIV therapy regime used if a woman is not taking antiretrovirals at time of pregnancy?
START (short-term anti-retroviral therapy) - a HAART regime starting between weeks 20 and 28 and being discontinued shortly after delivery
129
Which anti-malarial chemo-prophylaxis is safe to use in pregnancy?
Malarone
| Mefloquine
130
What would be the choices for malarial treatment in pregnancy in the UK?
Quinine
| Artesunate
131
How is oxytocin excreted?
Bile
| Urine
132
What is the half-life of misoprostal?
40 mins
133
What are the side effects of misoprostal?
```
Uterine rupture
Uterine hyperstimulation
Amniotic fluid embolism
Diarrhoea
Vomiting
Headache
```
134
Which prostaglandin is used in PPH and termination of pregnancy?
Prostaglandin E1
135
Which receptors do ergometrine work on?
5HT1
Dopamine
alpha-adrenergic
136
What are the contraindications to atosiban?
```
Pre-eclampsia
Intrauterine death
Intrauterine infection
APH
Premature ROM after 30 weeks
```
137
Is nifedipine licensed in pregnancy?
No
138
What is the dual mechanism of action of methyldopa?
1. Centrally acting alpha-2-agonist
| 2. Competitive inhibitor of DOPA decarboxylase
139
Aside from IUGR, what is a side effect of labetalol?
Neonatal hypoglycaemia
140
What is the mechanism of action of labetalol?
Mixed alpha-1-beta blocker
141
What is the effect of thiazide diuretics in pregnancy?
Neonatal thrombocytopneia
142
What is the effect of statin in pregnancy?
CNS and limb defects
143
How much does AED use increase the risk of teratogenicity in pregnancy?
x3
144
What are the symptoms of neonatal BZD withdrawal syndrome?
1. Hypotonia
2. Reluctance to suckle
3. Cyanosis
4. Impaired metabolic response to cold stress
145
Is warfarin embryopathy dose-dependant?
Yes
146
What is the antidote to unfractionated heparin?
Protamine sulphate
147
What can PPIs cause in pregnancy?
Anencepahly
148
What can antacids in pregnancy cause?
Milk-alkali syndrome
149
Where dose loperamide act?
Opioid receptors of the large bowel
150
What is the affect of NSAIDs?
Inhibits prostaglandin synthesis by inhibiting COX1 and COX2
151
What are the side effects if 5-ASAs used in pregnancy in mother's with UC/Crohn's
Agranulocytosis
| Hypospermia
152
Why is PTU preferred over carbimazole in pregnancy?
Lower placental transfer and excretion in breast milk
153
What are the uses of mifepristone?
1. EC - delays ovulation and prevents implantation
| 2. TOP (600mg) - up to 9/40
154
What are the contraindications of mifepristone?
1. Severe asthma
2. Chronic renal failure
3. Ectopic
4. Acute porphyria
5. Hepatic impairment
155
What is the most effective form of contraception, and its pearl index?
Implanon at PI <0.1
156
When can a COCP be used in breastfeeding vs. non-breastfeeding women?
```
Breastfeeding = >6 weeks post-partum ( but can reduce breast milk output)
Non-breastfeeding = >3 weeks post-partum
```
157
What are the differences in dosing between high, standard and low strength oestrogen with regard to COCP?
```
Low = 20 micrograms
Standard = 30-35 grams
High = 50 micrograms
```
158
Describe first generation COCPs:
High strength oestrogen 50 micrograms
159
Describe second generation COCPs:
Standard strength oestrogen 30-35 micrograms
160
Describe third generation COCPs:
Contain new-type progesterones
161
What are the risks of new-type progesterones used in third generation COCPs?
Increased VTE risk
162
What are the advantages of new-type progesterones used in third generation COCPs?
Reduced acne, weight gain, breast symptoms, headache and breakthrough bleeding
163
What are the first and second generation progesterones?
Levonorgestrel
| Norethisterone
164
What are the third generation progesterones?
Desoegestrel
| Gestodene
165
What are the missed pill rules in COCP?
If missed <3 (2 in low-strength oestrogen COCP) - take missed pill, no need for extra precautions
If missed >3 pills (2 in low-strength oestrogen COCP) - take missed pill, extra-precautions for 7 days, if in 3rd week, omit pill-free week, if in 1st week, use EC
166
By how much is the risk of endometrial and ovarian cancer risk reduced by COCP?
Endometrial - 50% reduced risk, and remains reduced for >20 years after stopping COCP
Ovarian - 40-80% reduced risk in a >10 year user
167
Which cancers do COCP increase the risk of?
Breast and cervical cancer
168
What are the missed pill rules with POP?
Take missed or late pill (>3 hours with all POPs except cerazette when only late if >12hours delay), extra pre-caution for 48 hours
169
What are the bleeding patterns seen in POP?
Amenorrhoea - 20%
Regular bleeding - 40%
Erratic bleeding - 40%
170
When may women not breastfeeding have Depo-provera injection for contraception?
5 days post-partum
171
What are the side effects of Depo?
1. Weight gain - 2kg/year in 70%
2. Osteoporosis - should not be used for >2 years
3. Delay in return of fertility for 6-18 months
172
When are peak progesterone levels after insertion of the implanon?
1-13 days
173
When are ovulation-inhibiting levels of progesterone reached on insertion of the implanon?
Within 24 hours
174
What proportion of women ovulate within 3 weeks of implanon removal?
90%
175
When is the copper coil effective after insertion?
Effective immediately
176
When is the Mirena coil effective after insertion?
If on day 1 cycle, immediately, otherwise, requires 7 days of precautions
177
What are the complications of IUDs?
1. 5% risk of expulsion, esp. in first 3/12
2. Uterine perf - 1/1000
3. Pelvic infection - risk greatest in first 20 days
