Dr. Jeffrey Klein advises avoid drug interactions with lidocaine with drugs that block lidocaine metabolism.
Safety tip number nine avoid drug interactions with lidocaine by that impair cytochrome p450 3 a 4 and 1 a 2 lidocaine is metabolized by a set of microsomal hepatic enzymes cytochrome p450 enzymes and these iso enzymes the are responsible for metabolizing lidocaine are cytochrome p450 3 a 4 and 1 a 2 we usually say to cyp3a4 for example and now there are certain
Drugs that patients may be taking that inhibit these enzymes if that happens to be the case that the patient is on a medication that actually retards the rate of lidocaine metabolism then normally safe dosage of tumescent lidocaine can become somewhat toxic so we need to be very careful to avoid drugs that cause inhibit or block lidocaine metabolism i have a list
Of drugs you all mentioned them but it is important to to be aware of the drugs that the patients are taking before they come into the surgery if there are on a drug that cannot be discontinued for one reason or another and it is a potential inhibitor of a strong inhibitor of lidocaine metabolism then the dosage of tumescent anesthesia should be reduced say from 45
Milligrams per kilogram to 35 milligrams per kilogram alize what we’ll often do in the situation like that now the discover some of the drugs that are associated with cyp3a4 metabolism inhibition so mithra mice and then clarithromycin biaxin are are common drugs taken by patients and these are very strongly inhibit i became metabolism chloramphenicol anti viral
Protease inhibitors that are often used by hiv patients sertraline or zoloft is another drug that the strong inhibition of like a metabolism we we published the first report of drug interactions with tumescent lidocaine and other medications and it was zoloft that a patient had taken sheila we had a patient who was given at this point in time we we hadn’t really
Decided with the maximum safe dosage was so weird she received 59 milligrams per kilogram of lidocaine on one occasion and had no problems on the second occasion that a month or two later she came back for another procedure and the same dosage of tumescent lidocaine but in the interim she had begun zoloft and this time she developed a mild of i became toxicity
That involved the dysarthria ataxia and some blurred vision because she was transferred to hospitals and observed overnight there were no further problems and she was dismissed the next one discharged next morning but that was a event that was worthy of publication so now we’ve become aware of all the drugs that can cause lidocaine and metabolism to change and
Slow down the other ones antifungals ketoconazole itraconazole buchanan’s all may be used as outpatient and those can cause problems there was one patient who came in to the surgery for the one of my colleagues told me about this patient was asked are you taking any of these drugs and the person said no but in fact they were just getting over an upper respiratory
Tract infection and had been on erythromycin until the night before surgery so she had taken this right up the patient of taking this right up to the day of surgery and then discontinued it and on the morning and surgery when she was asked if she taken any these drugs she said no and this patient also had a very mild form of lidocaine toxicity the same mild ataxia
Dysarthria and was observed overnight and no further problems occurred but that was that’s a pitfall that can happen so be very careful to question patients before tumescent anesthesia to make sure they’re not taking any of these drugs the other enzyme that is important is one a two and c prophylaxis and levofloxacin are drugs that inhibit lidocaine metabolism as
Is fluoxetine or love ox which is this antidepressant so those are drugs that should be on your list of no no’s i’m dr. jeffrey kline thank you for watching this informational video
Transcribed from video
Tumescent Safety Tips Lidocaine Drug Interactions By HK Surgical