High resting heart rate please help

[LifesTooShortYOLO]

So I've been in bed all day today with diarrhoea and vomiting with tummy cramps unable to keep even any water or fluids down.
GP says there's are loads of sickness bugs going around especially the norovirus and has prescribed me some anti sickness tablets.
I am dehydrated and have a headache as I haven't been able to drink anything since last night.
I have noticed that my resting heart rate is high today on my FitBit (confirmed with finger pulse oximeter) it's been above 100 all day while I've been resting in bed.
I'm waiting on a call back from 111 but just wondered if anyone had any reasons for why it may be high? I did read online that you get an elevated heart rate if your dehydrated so I'm hoping it's this 🤨 can't help but worry though.

Sounds like hypovolaemia (reduced blood volume) resulting from dehydration. Your heart beats faster/harder to try to get your blood pressure back up to where it should be.

What did you mean by "anti sickness tablets"? Anti-emetics aren't usually recommended in gastroenteritis. Were you prescribed something to help you keep oral rehydration salts down?

Thanks for your reply,
Yes because I was unable to keep any fluid or rehydration salts down he prescribed Prochlorperazine buccal tablets.
Why are they not usually prescribed for sickness bugs?

You wouldn't usually give drugs for viral gastroenteritis as it generally resolves itself within a couple of days and it's not worth the risks that are always associated with using drugs. Also, the diarrhoea and vomiting are a kind of defence mechanism to get the virus out of your body.

Normally, you'd only intervene with treatments if there's a risk of severe dehydration: a more significant risk in young children than in adults. The intervention then would be to give oral rehydration salts (a mix of water, salts and glucose: the glucose is required for the sodium to be absorbed, and it's the sdium absorption that allows water to be absorbed).

Of course, if you're vomiting up the oral rehydration solution it's not going to achieve anything, so you might then be given an anti-emetic to give the water & salts a chance to be absorbed. And, as you've found, the anti-emetic needs to be in a form that's absorbed from the mouth because tablets that are swallowed will also just be vomited back up again. But giving the anti-emetic without the oral rehydration salts also isn't going to achieve much.

With norovirus, your body doesn’t actually need to vomit, it’s just something we have developed through the years as an instinct, your body will be fighting of the virus inside so you don’t need to vomit for it to resolve

You can definitely use anti emetics in norovirus. We regularly use ondansetron (the only anti emetic you can use in young children) to avoid having to stick needles in them to put a drip up, if they can't tolerate little and often of oral rehydration solution. What you're not meant to give is anti diarrhoeal agents.

What anti sickness tablets do you have? Cyclozine for instance have a potential side effect of an elevated heart rate. ‘It[s rare but it happens, it happened to me, and I now have a “no cyclozine” note on my records.

I get ondansetron prescribed and it's a god send