H2 receptor antagonists

Question 1

cautions for all h2ra

Answer 1

they may mask the signs and symptoms of gastric cancer
particular care needed in pt presenting with alarm features - rule of gastric malignancy before treatment

Question 2

pt who regularly takes famotidine has been prescribed ketoconazole/itraconazole. what would you advise

Answer 2

Famotidine is predicted to decrease the absorption of Ketoconazole. Manufacturer advises administer Ketoconazole with an acidic beverage.

Question 3

true or false - they can affect EHC

Answer 3

true. they can decrease the efficacy of ulipristal

Question 4

7 common SE for all h2ra include

Answer 4

Constipation; diarrhoea; dizziness; fatigue; headache; myalgia; skin reactions

Question 5

can you use in preg or BF

Answer 5

avoid

Question 6

cimetidine interaction with coumarins

Answer 6

acenocoumarol, warfarin, pheninidone

it increases the AC effect.

Question 7

cimetidine interacts with this high risk drug commonly used in asthma. what is the interaction

Answer 7

Cimetidine increases the concentration of Aminophylline. Manufacturer advises adjust dose.

Question 8

cimetidine and 3Ps1C, fosphenytoin

Answer 8

Cimetidine transiently increases the concentration of Carbamazepine. Manufacturer advises monitor concentration and adjust dose.

Question 9

cimetidine and citalopram, escitalopram

Answer 9

Cimetidine slightly increases the exposure to Citalopram. Manufacturer advises adjust dose.

Question 10

cimetidine and diltiazem

Answer 10

Cimetidine slightly increases the exposure to Diltiazem. Manufacturer advises monitor and adjust dose.

Question 11

cimetidine and TCAs - amitrip, dosulepin, dose-in etc

Answer 11

Cimetidine increases the exposure to Dosulepin. Manufacturer makes no recommendation.

Question 12

cimetidine and erythromycin

Answer 12

Cimetidine slightly increases the exposure to Erythromycin. Manufacturer makes no recommendation.

Question 13

cimetidine interacts with this opioid used for severe pain

Answer 13

Cimetidine might increase the exposure to Fentanyl. Manufacturer advises monitor and adjust dose.

Question 14

amidarone, flecainide, lidocaine, propafenone and cimetidine

Answer 14

Cimetidine slightly increases the exposure to Flecainide. Manufacturer advises monitor and adjust dose.

Question 15

cimetidine interact with itraconazole , ketoconazole

Answer 15

Cimetidine is predicted to decrease the absorption of Itraconazole. Manufacturer advises administer Itraconazole capsules with an acidic beverage.

Question 16

cimetidine interaction with nifedipine

Answer 16

cimetidine moderately increases the exposure to Nifedipine. Manufacturer advises monitor and adjust dose.

Question 17

cimetidine interaction with quinine, chloroquine, hydroxyquinine

Answer 17

Cimetidine slightly increases the exposure to Quinine. Manufacturer makes no recommendation.

Question 18

if cimetidine is used in HI, there is increased risk of what side effect

Answer 18

confusion

Question 19

due to safety concerns about a contaminant, all formulations of this h2ra are currently unavailable in the UK
no new pt to be initiated on treatment with it!

Answer 19

ranitidine

Question 20

does cimetidine interact with antidepressants e.g. mirtazapine, paroxetine, sertraline

Answer 20

yes increases exposure