If it's a steroid nasal spray, which I'm assuming it is, they can take up to 5 days to kick in. I was told to take Sudafed (the kind you need to show your driver's license to buy) every 4-6 hrs - unless you have hypertension or heart issues.
Yes, it can take awhile. For me it was about 2 weeks. Keep blowing your nose (not too hard) and swallowing.
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