Can Claritin d give a false positive on a drug test?

There is always a chance certain meds will give you a false positive. Claritin has pseudophedrine in it which is basically the unreduced from of crystal meth. This is very commonly mistaken on drug tests however, if It is for a legal case you can request that they have your drug test sent to a lab, and you can show them your OTC meds you've been taking.
If it is for work, school or your parents are paranoid then tell them you've taken claritin/pseudofed and tell them that if they don't you believe you, pay the 300 dollar price to send it to a lab. That ought to dismiss their doubts or at least get them off your back.