Two interactions to know 1. Beware of foods rich in vitamin K
Brassicaceae (cabbage , broccoli , spinach ...) , avocado , parsley , lettuce , green tea and offal packed with vitamin K. They are to eat sparingly (no more than one serving "reasonable" daily , limiting consumption of sudden changes) if we take the same time oral anticoagulants (vitamin K antagonists in the long term) to thin the blood .
Decreasing the effectiveness of anticoagulants , these foods are at risk of thrombosis.
2. Attention to citrus
Grapefruit juice , one of Seville oranges and tangelos contains two flavonoids (naringin and naringenin) which inhibit:
- A cytochrome P450 isoenzyme , CYP3A4 , very involved in the metabolism of many drugs ,
- And intestinal protein (P-glycoprotein).
a - This inhibition results in increased blood concentrations of drugs such as cyclosporine (immunosuppressant used against transplant rejection) with a risk of kidney damage.
Note: a glass of grapefruit juice three levels of cyclosporine
b - It also increases the blood levels of some statins used for lowering blood cholesterol: simvastatin , atorvastatin to a lesser extent. The risk of myopathy cause profound because citrus remains theoretical in people treated. In general it is just muscle pain. Similarly , the risk of acute renal failure by grapefruit interaction / statin remains theoretical.
Note: A grapefruit juice taken with simvastatin can multiply that by 15 drug absorption.
c - The plasma concentration of certain antihypertensive calcium channel blockers may also increase (felodipine , nisoldipine , for example) with a risk of hypotension mainly.
Note: A glass of grapefruit juice increased the peak plasma concentration of felodipine on average 300% of nisoldipine on average 500%.
d - A glass of grapefruit juice can increase:
- Levels of terfenadine (antihistamine) of 450%.
- Levels of ethinyl estradiol (estrogen birth control pills)
- Midazolam (benzodiazepine psycholeptic , sedative)
- Of the antiviral agent saquinavir.
In addition , citrus fruits (lemon , grapefruit , orange) should be avoided with anti-inflammatories or aspirin , otherwise increase or trigger heartburn or acid reflux.
Three practical advice 1 - avoid drinking grapefruit juice within two hours before the medication ,
2 - limit consumption to less than a quarter of a liter per day
3 - swallow its anti-inflammatory in the middle of the meal.
