I used to get really severe rhinitis (hayfever/grass pollen allergy). Even with strong prescription meds high pollen days were terrible with watering eyes, a continuously running nose and itchy painful palate. I used to take Telfast, which is only available on prescription now, but even that didn't help much. There were days when I could hardly breathe, and lay in a darkened room with the windows closed, and a wet flannel over my face to try to filter out pollen. I couldn't walk through parks or in the countryside. Telfast is stronger than the over the counter hayfever remedies, but it did make me sleepy. I also took a painkiller like paracetomol or nurofen to ease the painful palate.
I used to volunteer for every hayfever treatment trial I saw advertised. About 7 years ago I did one where I took grass pollen tablets for 12 weeks before the grass pollen season and during it, which desensitises you. It was amazing, apart from an occasional sneeze, I had no symptoms that year, and my hayfever has been less severe since then, and I just use pharmacy pills (Loratadine) now.
The grass pollen pills are now available, called Grazax. But the NHS won't prescribe them as they cost £2 a day, though they might for children. If you take them continuously for 2 years they are supposed to desensitise you completely. I did consider getting them privately, but that costs £100 for a private consultation, and you have to take the first pill under medical supervision as it can cause anaphylactic shock in some people. It then costs around £250 a month. If my hayfever was still as severe as it used to be I would pay that, but as it's not so bad now I think that is more than I would be prepared to pay. If I could pay the NHS the £60 a month it costs them, I would happily pay that, but that is not possible.
Do you find your bs meter readings and HbA1c go up during the hayfever season?