Sorry for the late response but i was offline. Now from the symptoms which you are describing there can be a number of conditions which can cause these sort of symptoms. While a nerve agent can cause similar symptoms it is unlikely to be a nerve agent as 99% of all nerve agents would causes rapidly progressive symptoms which would worsen and you would develop breathing issues almost immediately after ingesting or coming into contact with the agent. Now given your symptoms it is possible that you have been exposed to organosphosphates which can cause symptoms like the drooling, watering eyes as well as the muscle twitching. It is possible that you have some organophosphates in your environment and you regularly come into contact with them which is causing these symptoms. A good way to determine this would be to check the immediate area and see if you havce any pesticides etc which can come into contact with your skin.
Now apart from organophosphates, it is possible that you have a neurological disorder which is causing these problems. Many neurological disorders can lead to these symptoms especiually the muscle twitching and this would be easily identified with the help of simple tests like MRI of the spine or even a NCS/EMG test. In addition many electrolytes imbalances can also cause this problem and those can be diagnosed on the basis of a simple blood test.
Now as far as treatment is concerned, it depends on the actual cause of these symptoms. Most of the causes which i have mentioned above are entirely treatable. Even if it is due to a nerve agent which i doubt given the duration of your symptoms, it can still be treated depending on the type and amount of exposure that you had. The best way to go about this would be to see your doctor and have him examine you and run a few tests, once the cause is determined you can be started on treatment which may involve antidotes etc depending on the actual underlying problem.
Do you have any more questions?
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