After I started on ipi/nivo in January I noticed I started drinking copious amounts of tea. I was relieved there were no immediate side effects, the ones they warn you about; diarrhoea, sickness, itching, so I just thought it was a funny aside, hahaha. A few weeks later I was finding my thirst incessant and I became inseparable from my water bottle(s). I got so fed up with it! Not so funny now, eh?! Initially we believed it was due to the decline in my kidney function, but once the kidney returned to acceptable levels and my thirst didn’t return to normal, my patience ran out. I was also getting fed up of my frequent visits to the loo, both the domestic and the “wild” variety.
My first search for an answer was to diabetes insipidus but my oncologist was certain it wasn’t this. Sjogren's syndrome had been on the radar when I first reported the excessive thirst too, but I didn’t have dry eyes or a mouth that felt dry either.
The game changer came in June when I started having problems chewing (bread, cake, biscuits, cheese). Bits of bread would end up stuck in my mouth and gums.
Dry mouth is listed as a possible side effect of immunotherapy drugs so I suggested this to my oncologist as a driver for my thirst. “Good shout, try eating pineapple and Bassett’s jelly babies” he said. Now, I like my oncologist, a lot. He’s a great listener, he knows when to shut-up, and he patiently accommodates all my questions. But I felt this was the silliest thing he has ever said, a most unlikely remedy. A bit unfair you might be thinking? Having read multiple accounts on reliable internet sources about dry mouth, none of them mention pineapple as a potential relief. I dutifully tried it out. I ate a whole tin (400g) the next day and then snacked on it over the next two days. I tried small amounts and frequently. I tried sucking it. I tried jelly babies but they hurt my teeth – another issue to deal with lol. Nothing bought any noticeable change to my thirst.
A few days later I was at my GP for a catch-up armed with the print-out of NICE recommended medications to relieve dry mouth and the personal recommendations from the Macmillan Head and Neck forum (thanks guys!). To cut a long story short I have now tried:
(a) Salivix lozenges (£5 for 50)
(b) Glandosane (on prescription) mouth spray. Lemon flavour.
(c) Oralieve moisturising mouth gel (£8 for 50ml). Too sweet.
(d) Xylimelts (OraCoat) 25+p each but you can only buy them in bulk in £10 increments. Natural flavour. A front runner. These really do seem to work.
(e) BioXtra Mild Mouthwash for dry mouth (£7.85 for 250ml, special order from my local pharmacy)
Whilst it does feel like there is some improvement, the core problem remains. Now I sometimes experience dry lips, an occasional sticky mouth, and talking will invoke thirst too. I still can’t chew dry food easily. I don’t understand why the symptom is a dry mouth for everyone else, but my experience is constant thirst. Very weird! Perhaps my brain is wired differently to everyone else. 
I was at the dentist and she confirmed the dry mouth diagnosis. Relief! In her experience, people didn’t find the remedies any good for a prolonged period (>5 mins). You’ve got to love a bit of pragmatic advice, even on hearsay. It looks like I will need to learn to adapt to it. The issue is that insufficient saliva impacts your first line of defence for oral health meaning I’m more at risk of tooth decay and gum disease. Since this sh1tshow started, I’ve gained a personal relationship with my GP and my oncologists and I’m in no rush to add a dentist to this list. 
So, what to do?!
Some of the recommendations for dealing with this are pretty cr@p and unrealistic, like change your diet, and don’t drink caffeine and alcohol. Bollocks to that. 
But I have found some reasonable adjustments:
1/ Upped my oral health regime – my teeth have never felt so loved. 
2/ Swapped my orange squash hydration regime with water. Because I’m drinking all the time, the dentist advises the constant sugar in contact with my teeth heightens the risk and therefore water is the hydration of choice. Hmmmmmm. . . . We’ll see how I get on with this.
3/ Mental preparation and anticipation for eating cake and bread. I found myself sucking my vanilla cake and trying different chewing techniques moving the food around my mouth desperately seeking a successful chew lol.
I am continuing with the dry mouth relievers. I’m trying to find out the best one(s) for me.
To continue my little humorous “game” with oncology and my cancer, I was 1-2 down, but as the “dry mouth” was my suggestion, I now draw level at 2-2. GET IN!!
In conclusion, it’s another example of the impact of cancer and immunotherapy drugs.
