The "D" part is pseudephedrine. At one time, this was all we could use for sinuses and allow one to fly.
Yes, it is allowed. Claritin-D is a prescription item so you will have a co-pay ($$ depends on your insurance plan). Generic Claritin at Costco here is $11.56 for 300 tablets - that is less than my co-pay and lasts nearly a year. Insurance will not give you more than 90 days of medication at a time (more co-pays), so go with the large volume generic bottles. Also check the generic prices - some large pharmacy chains charge $1.00 a pill for generic Claritin.
One thing that now is a hassle is the removal of pseudephedrine from the open shelves (used to make methamphetamine). In Phoenix you have to see the pharmacist, have an ID and sign for it.
