hello and welcome to HCM,
Splenda is artificial sweetener sucralose
and i very frequently used to give artificial sweetening to food products. Although reports are not very consistent, it has been suggested that splenda can have many side effects which can include what you are experiencing.
In any case you may use splenda in limited quantity and nothing will happen, but if you use anything in the quantity you mentioned then definitely it may cause so much of side effects.
As far as your tinnitus
is concerned, you need to immediately stop splenda and get an audiometry
done. You need to take a multivitamin
tablet like zincovit
once daily after food and a steroid tablet like the predmed in doses of 8mg three times for two weeks immediately. Your doctor will know about this.
It usually takes around two weeks to two months for the effects to go so you need to wait for such time to feel better.
Dr Sriram Nathan