Thursday, March 18, 2010
The perils of grapefruit juice and rational thinking about drugs
With all the uproars about Mephedrone, should we also be thinking about another totally legal product with definite dangers – grapefruit juice?
Well, dangers if you are taking certain medicines to control high blood pressure. Grapefruit juice contains furanocoumarins, chemicals that inhibit certain enzmes in the gut. These enzymes partially destroy the active ingredients in statins (chloresterol-reduction drugs) and in ‘calcium channel blockers’ (drugs that directly reduce blood pressure). The dosage for each patient is prescribed on the assumption that these enzymes are working normally. Inhibition means that the patient actually takes in a higher dose of the drug than intended and can unexpectedly suffer substantial side-effects.
The NHS says that
I doubt whether many people will call for grapefruit juice to be taken off shop shelves …
Hat tip to Caron for digging up this link to a statement by Prof David Nutt on the present Mephedrone uproar, and it seems we can look forwards to the webpage for the new ‘Independent Scientific Committee on Drugs’ going live in a couple of weeks. In time for the election on other words and lets hope this new resource reduces the temptation of some ‘Old And Sad’ smear-mongers to do ‘soft on drugs’ stories on some of us…
The ISCD says it was founded by Professor Nutt
Webpage planned to be http://www.drugscience.org.uk/ (you only get a domain notice at time of posting this).
The interactions of this and that chemical in the human body are a wonderous thing!
Well, dangers if you are taking certain medicines to control high blood pressure. Grapefruit juice contains furanocoumarins, chemicals that inhibit certain enzmes in the gut. These enzymes partially destroy the active ingredients in statins (chloresterol-reduction drugs) and in ‘calcium channel blockers’ (drugs that directly reduce blood pressure). The dosage for each patient is prescribed on the assumption that these enzymes are working normally. Inhibition means that the patient actually takes in a higher dose of the drug than intended and can unexpectedly suffer substantial side-effects.
The NHS says that
Drinking grapefruit juice whilst taking calcium channel blockers can lead to low blood pressure, increased heart rate, dizziness, flushing and headaches.
Whether or not you can drink grapefruit juice without experiencing these effects depends very much upon you as an individual. One person might be affected in a very different way to another, even though they are on the same dose of calcium channel blockers and drinking the same amount of grapefruit juice.
The reaction depends not only on the dose and on the individual, but also on whether you are a regular, long-term grapefruit juice drinker….
….. If you are taking felodipine, nicardipine, nimodipine, or nisoldipine you should avoid drinking grapefruit juice altogether.
I doubt whether many people will call for grapefruit juice to be taken off shop shelves …
Hat tip to Caron for digging up this link to a statement by Prof David Nutt on the present Mephedrone uproar, and it seems we can look forwards to the webpage for the new ‘Independent Scientific Committee on Drugs’ going live in a couple of weeks. In time for the election on other words and lets hope this new resource reduces the temptation of some ‘Old And Sad’ smear-mongers to do ‘soft on drugs’ stories on some of us…
The ISCD says it was founded by Professor Nutt
.... to objectively review and investigate the scientific evidence of drug harms free from political concerns. All too often, crucial information on the effects of drugs is buried away in arcane scientific journals and the debates of expert groups. The Committee will provide accessible information on drugs to the wider public and engage in an ongoing dialogue.
Webpage planned to be http://www.drugscience.org.uk/ (you only get a domain notice at time of posting this).
The interactions of this and that chemical in the human body are a wonderous thing!
Comments:
Post a Comment