I take 3 medications that metabolize by the same liver enzyme cyp2d6. A drug interaction checker told me that on or two of the medications i take may slow metabolism of another by altering drug metabolism. Ive had no side effects or interactions from this combination of drugs. Ive also read of people being on the same combination of drugs with no problems. If a drug is considered an enzyme inhibitor, is it a definite that it will slow metabolism and raise blood levels of another drug, or is this just a possibility? Thanks for any feedback

  • $\begingroup$ The interaction checker is flagging those drugs for a physician/pharmacist to monitor and make a treatment decision on. It does not mean "people that take these two drugs will die immediately." It might mean "people that take these two drugs together are more likely to see rare side effects" or "people that take these two drugs together might have a lower blood pressure on average" - without more information you can't know. $\endgroup$ – Bryan Krause Sep 1 '17 at 23:13
  • $\begingroup$ It is unlikely that any of the drugs are enzyme inhibitors. Generally the drugs can interact by competing for the use of the CYP2D6 enzymes for the period needed for enzymatic activity (usually quite short for each molecule of a drug or other compound, other than inhibitors). $\endgroup$ – mgkrebbs Sep 2 '17 at 0:59
  • $\begingroup$ My main question is that the interaction checker states that two drugs i take may or can alter the metabolism of a third drug i take. To me this means only a possibility, and won't necessarily happen. Hence, using the words may and can. Is this the way others here understand this? $\endgroup$ – crrjmn Sep 3 '17 at 18:30

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