My Husband Is 54 Yrs Old. He's Having A Hard

my husband is 54 yrs old. He's having a hard time breathing.. very winded and has head congestion. No fever. He has seasonal allergies and usually waits until he's miserable before he takes his allergy medicine. He is currently taking Zyrtex. hasn't taken it for a couple of days. He says he can feel his sinuses draining into his throat. and has a sore throat.