Congestion, nausea, fatigue. I ve been suffering with allergies for the last two years and continuously taking Zyrtec or Benadryl. I stopped all meds for the last 4 months but for about 6 weeks now I cannot breath through my nose. My nose is a little runny in the morning but no other symptoms. However, I started nasal irrigation the last two days, twice a day and now feel worse!!! I feel very tired with nausea and no relief from my congestion.