As discussed, the thick mucus or rope mucus mainly goes away 2-4 weeks after radiation treatment ceases, when the saliva glands, mainly Parotid, starts producing more thin saliva, which radiation mostly effects, and the two other major salivary glands, and hundreds of minor salivary glands in the mouth and throat compensate for the loss, and a reason why we have more thick mucus until then. IMRT is designed to be salivary gland sparing, and the radiation dosage, less than 30Gy, Volume, less than 50%, is usually planned so they may recover, and in some trials, are not radiated or only one side of the head and neck instead of bilaterally depending on varying factors.

Treatments, including chemo, have acute, less than 3 months, and long term toxicities, longer than 3 months, and It may take up to 2 years to fully recover from some, like salivary glands, although now at 6 years with various treatments I still have some that are on going, dry mouth, others new or being newly addressed, but can say it does get better, and most things will be a blur as more time goes bye, and felt differences at 3 months, 6 months, 1 year intervals maybe that coincided with my doctor visits/scans.

As far as thick mucous, I have tried a number of things, through several of my treatments and after treatments. Milk does not cause thick mucous. Its enzymes replicates saliva, coats the mouth, gives a feeling of such. I couldn't drink milk, ice cream, even yogurt, for years, since the lactic acid burned my mouth, plus having altered sweet taste.

Sleeping on an Incline
A humidifier as mentioned
A warm shower
Hot soup
Drinking often
Rinsing with or drinking pineapple, papaya juice, now I drink beer occasionally!
Rinsing with brewed tea
NeuraSal, a prescription rinse which helps with mucocitus and dry mouth
Having the radiation center spray my mouth out with saline solution
Brushing often, tongue, gums too, gently with bristles softened with warm water
I've only used a suction machine in the hospital
Oral sponge brushes to get in the mouth, get out thick mucus, brush teeth with

10/09 T1N2bM0 Tonsil
11/09 Taxo Cisp 5-FU, 6 Months Hosp
01/11 35 IMRT 70Gy 7 Wks
06/11 30 HBO
08/11 RND PNI
06/12 SND PNI LVI
08/12 RND Pec Flap IORT 12 Gy
10/12 25 IMRT 50Gy 6 Wks Taxo Erbitux
10/13 SND
10/13 TBO/Angiograph
10/13 RND Carotid Remove IORT 10Gy PNI
12/13 25 Protons 50Gy 6 Wks Carbo
11/14 All Teeth Extract 30 HBO
03/15 Sequestromy Buccal Flap ORN
09/16 Mandibulectomy Fib Flap Sternotomy
04/17 Regraft hypergranulation Donor Site
06/17 Heart Attack Stent
02/19 Finally Cancer Free Took 10 yrs