I'm not sure about phenylephrine, but if it does, their tests are poor. However, desoxyephedrine is methamphetamine, so of course it would make you test positive.
No.
No, meth will make you test positive for meth.
Meth and marijuana
Assuming you mean Xanex, you will not test positive for meth. Xanex is a benodiazapine so you will test positive for those.
Uh, having methamphetamine in your system! But other sources say the following can also cause false positive results: Desoxyephedrine, Desoxyn, Methedrine, Vicks Inhaler (non-prescription drug), Selegiline, Benzphetamine and Famprofazon, Dexedrine, Benzedrine, Adderal.
meth
No
No.
yes
Yes
The Mr clean commercial
Yes you can absolutely test positive for meth using Lipozene
No, Zyrtec does not contain any ephedrine/psyeudoephedrine ingredients.