taking mucinex first trimester

so i have a very bad cold pretty much, i was negative for covid and the flu. i went to urgent care just now and they told me i could take regular mucinex just avoid mucinex d or mucinex dm, i thought you couldn’t take any mucinex during the first trimester ? i guess i’ll have to wait to double check with my OB tmrw but does anybody know if this is true ?