I have an allergy of synflex can I take coricidin?

Coricidin wouldn't have any glucosamine in it.

It would completely depend on what ingredient in Synflex you are allergic to and whether or not it is also in Coricidin.

Synflex contains glucosamine, chondroitin, Manganese, Vitamins A,C & E, Omega 3 & 6, Boswellin, Bromellain, Yucca and White willow bark (Salicin - aka salicylic acid the active ingredient in Aspirin). It likely also contains several fillers and binders that are not listed.

Coricidin lists its ingredients as chlorpheniramine and acetaminophen. Also likely to contain fillers and binders. Again not listed and not necessarily known.
Always take care when trying a new medication, and talk to your doctor. Allergies can be deadly if severe enough.