Extreme Dry Mouth

As posted before since August I Have been on Tamsulosin Hydrochloride for BPH. Unfortunately the twin side effects of dry mouth and nasal congestion have continued to escalate and are now serious. The nasal congestion prevents me from using a nasal mask anymore so I have aquired several new full face new style masks (dreamwear, resmed airfit and the hybrid) these are great and I end up mouth breathing. However, constantly mouth breathing whilst using cpap creates a serious medical condition where your lips and tongue stick to your teeth. I am expecting many people out there to have experienced this and would welcome their advice on what worked for them. I am at my wits end and only find some slight relief using synthetic saliva spray. I should add that I saw my GP who prescribed steroid nasal spray which might provide some answers but will take up to 6 weeks to click in. There is also a chance that the nose blockage uis due to polyps although the GP did not diagnose this. I have to find the answer to this as I am sitting up most nights because being verticle helps but of course it is without the cpap which most definitely worsens the dry mouth. Interestingly, my throat is not dry and my nose is completely blocked but clear of mucus.