Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concern..
As per your complain you are suffering from viral
throat infection and along with it the white fur like coating seems to be
fungal infection known as
ORAL THRUSH and is not due to accumulation of debris from cough drops but due to fungal overgrowth..
Nothing to worry start using
Nystatin mouthwash and gargle 3 to 4 times a day..
Take more of probiotics like Yoghurt and garlic.
Do it for 2 weeks and gradually the coating will start clearing off.
In case if it does not improve consult an oral physician and get evaluated and if required he can advise you to take oral anti-fungal medicines like
Fluconazole.
For congestion take decongestant medicines like pseudoephdrine [sudfed]
Do steam inhalations and use a cool mist humidifier in your room..
Avoid antibiotics and oral and nasal steroids as they can increase the thrush..
Hope this information helps..
Thanks and regards..
Dr.Honey Nandwani Arora.