I took claritin (loratadine) but i meant to take claritin (loratadine) d. can i take claritin (loratadine) d in a few hours?? i'm so congested

No: Take claritin d the next day. Ocean spray nasal rinses work good to help relieve symptoms in the interim.

Not a good idea: It is not a good idea to take two claritin (loratadine) that close together. It is really a once a day drug. You could take some separate decongestant if you wanted to, like sudafed, something that does not also have antihistamine in it. Hope you feel better soon.

Claritin (loratadine): The recommended daily dose of claritin (loratadine) is 10mg a day, so the by the book answer is no, you should not… Many people though need more antihistamine than that when having an allergic reaction so you it is possible and safe to take an extra 10mg, but I would suggest in your case is to buy some plain sudafed (the D in Clariitn in D) and take that two times today instead.

I would encourage: You to avoid to double dose, as while not the end of the world, you are more likely to suffer side effects like headaches, sedation, dry mouth, fatigue. Why not just take a dose of Sudafed to augment the Claritin (loratadine).