AboutNigel Simmons Expertise I am happy to answer general questions on medicines and hospital care. If possible, please use approved / chemical names rather than brands which are not internationally recognised.
Like all health professionals I am bound by a duty of care which prevents me giving detailed information about medication or treatment of people other than the questioner.
I will endeavour to help wherever possible or point towards more appropriate advice. If however your question crosses too far into patient confidentiality, I hope you will understand why I cannot answer your question.
Consider.. would you want me to discuss your care with a friend or relative without your knowledge?
Experience Registered as a UK pharmacist in 1982 and have worked in a number of hospital and health management posts around the UK. Formerly Chief Pharmacist for a 440 bed general hospital in Cambridgeshire.
Past/Present clients Previously Sysop on CompuServe UK Professionals forum.
Expert: Nigel Simmons Date: 3/24/2008 Subject: False Positive Drug Screen
Question I took 2 tablets of Benadryl sever allergy &sinus headache on the 23rd of March, took drug screen on the 24th of March could I possibly come up positive?
Answer Rachel
In theory the tests should be specific for the drugs they test for but there is some evidence that false results can occur due to other non-related drugs. Unfortunately there is no published list of drugs or tests, so it's impossible for me to give specific advice.
In addition, there is always a risk of poor storage or handling of samples leading to contamination or swapping of samples.
My recommendation would be to always see the sample tested in front of you with no others in the area to cause confusion. Ideally also get the details of the manaufacturer of the test strip and the batch number, as these may help if you do need to challenge an erroneous result. Keeping part of the sample for yourself (until the result is negative) would also allow you to get independent verification if you wanted.
Other advice would be to contact the manufacturers and ask them for information on false results with their product (your local pharmacist may do this if they won't talk directly to you); asking for an immediate blood test to confirm the result; and being extra careful to avoid any covert taking of drugs without your knowledge. If you can, getting your prescriptions from a local pharmacy rather than mail-order will also give confidence that the products are not adulterated by a dubious manufacturer. If at all possible, avoid taking any over the counter or other medicines (including herbals) and only use what a doctor prescribes - asking them to give you a letter to inform the clinic of what you are taking and why.
So, fingers crossed you will not have problems, but if the drug screen is a regular event and affects your employment or a legal issue, then it would be advisible to follow the safeguards I have suggested.
