Question 1

i took drug test today and it was positive for tca, i regularly take an otc sleep aid with diphenhydramine. couldn't have caused the false positive?

Accepted Answer

"tca"????: did you mean THC (marijuana or cannabis)?  TCA medically usually means tricyclic antidepressant, and these are actually chemically similar to benadryl (diphenhydramine).  If all that was done was a SCREENING test, there are lots of potential false positives, and if used for legal purposes, all screening tests should be confirmed with a more sophisticated test, usually gas chromatography/mass spectroscopy.

Question 2

never taken antidepressants but tested + for tca. i take prescribed vyvanse (lisdexamfetamine) & an otc diphenhydramine sleep aid only. can either have lead to a false +?

Accepted Answer

Benadryl (diphenhydramine) : If you do not take any tricyclic antidepressants, and have a positive TCA on a toxicology screen, is likely the diphenhydramine that you're taking, which can sometimes give a false positive for TCA.  If the Vyvanse (lisdexamfetamine) hinders your nighttime sleep, consider taking melatonin rather than diphenhydramine for long-term use.

Question 3

could taking 40+ benadryl (diphenhydramine) cause a positive for benzodiazepines in a urine test?

Accepted Answer

Shouldn't: They are made of totally different chemicals even though either can make you drowsy.

Question 4

i took one tylonal pm the has 25mg of benadryl (diphenhydramine) in it. i have a pre employment drug test in 12 hrs whats the chance of a false positive for pcp.

Accepted Answer

Not from either: Neither of these components is going to cause a positive PCP test.

Question 5

can diphenhydramine cause a false positive for meth?

Accepted Answer

No: no it can not cause false positive meth result

Question 6

i have taken 2 separate hair follicle test for new jobs both test came back positive for meth i have been clean for over 5 months. could one of these medications cause it? diphenhydramine reglan tordol zofran losartan?

Accepted Answer

: One detailed study showed that chronic meth use can be found in hair tests up to 153 days after being stopped. As for false positives with those meds listed,your pharmacist will possibly have that information but I'm dubious that they would test positive.

Question 7

does benadryl (diphenhydramine) cause you to fail a u.a?

Accepted Answer

NO: Benadryl (diphenhydramine) does not cause you to fail a drugs of abuse urinalysis.

Question 8

can taking benadryl cause acquired lqts?

Accepted Answer

Rarely.: In people who have congenital LQTS, benadryl can cause heart arrythmias by making their underlying problem worse. In people with normal QT, very large doses or overdoses of benadryl can prolong the QT and have serious or fatal consequences. Bendaryl is a medicine to avoid if you have LQTS, and only one of many factors to consider if you have the acquired version. Speak to a cardiologist.

Question 9

can stopping benadryl (diphenhydramine) after extended use cause side effects?

Accepted Answer

Not usually: It should not cause any issues.

Question 10

what are the tests for benadryl (diphenhydramine) overdose?

Accepted Answer

Clinical: It's a clinical diagnosis. It would require a special forensics lab to test specifically for it which isn't usually done.

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Doctor answers about:

Does benadryl cause false TCA test

A member asked:

I took drug test today and it was positive for tca, i regularly take an otc sleep aid with diphenhydramine. couldn't have caused the false positive?

A member asked:

Never taken antidepressants but tested + for tca. i take prescribed vyvanse (lisdexamfetamine) & an otc diphenhydramine sleep aid only. can either have lead to a false +?

A member asked:

Could taking 40+ benadryl (diphenhydramine) cause a positive for benzodiazepines in a urine test?

A member asked:

I took one tylonal pm the has 25mg of benadryl (diphenhydramine) in it. i have a pre employment drug test in 12 hrs whats the chance of a false positive for pcp.

A member asked:

Can diphenhydramine cause a false positive for meth?

A member asked:

I have taken 2 separate hair follicle test for new jobs both test came back positive for meth i have been clean for over 5 months. could one of these medications cause it? diphenhydramine reglan tordol zofran losartan?

A member asked:

Does benadryl (diphenhydramine) cause you to fail a u.a?

A member asked:

Can taking benadryl cause acquired lqts?

A member asked:

Can stopping benadryl (diphenhydramine) after extended use cause side effects?

A member asked:

What are the tests for benadryl (diphenhydramine) overdose?

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