You will have to take antihistamines for at least 15 days more.

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Brief Answer:
Yes , it a symptom of post nasal drip

Detailed Answer:
Thanks for asking a question.
Yes It can be even a symptom of post nasal drip. You can have it with post nasal drip ,causing your tongue to have a discolored look . This coating is a combination of mucus, sulfur compounds and in some cases, beverages and food particles. This could also be a source of bad breath.

Now let us discuss the treatment of this symptom in detail..
Treatment of Postnasal drip depend upon the cause of it.
Infection (associated with fever or pain or change in the color of mucus ) will have to be treated with antibiotics if it is bacterial . But green or yellow mucus is not necessarily proof of a bacterial infection. Colds can also turn the mucus these colors and they are caused by viruses, which don't respond to antibiotics.

Antihistamines and decongestants can help with postnasal drip caused by sinusitis and viral infections. Newer generation of Antihistamines don't cause much dryness or drowsiness . They can also be effective, along with steroid medications or nasal sprays, for postnasal drip caused by allergies.

Another treatment option for postnasal drip is to thin your mucus. Mucus can have different consistencies. Thick mucus is stickier and more likely to cause you discomfort. Keeping the mucus thin helps prevent blockages in the ears and sinuses, which can lead to infections. A simple remedy to thin mucus is to drink more water.

Other methods too can be tried :
--a mucus-thinning medication such as guaifenesin may be taken
---Using saline nasal sprays or nasal irrigation to flush excess mucus, bacteria, allergens, and other irritating substances out of the sinuses
---do steam inhalation
---Try propping up your pillows at night so that the mucus doesn't pool or collect in the back of your throat.
If you have allergies, ways to reduce the triggers which may be :
--Covering the mattresses and pillowcases with dust-proof covers
---Washing all sheets, pillowcases, and mattress covers often in hot water
--- Dusting and vacuuming regularly

Finally If medication isn't helping the postnasal drip,then you need to see an otolaryngologist (ENT Specialist ) for evaluation and further management.

Hope this helps.

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Brief Answer:
Common

Detailed Answer:
Yes, Post nasal drip is common and is associated with allergies to pollen and dust.
Nose can be dry too.

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Brief Answer:
Yes it may be one of the causes

Detailed Answer:
Thanks for your response.

Sinusitis is one of the causes, but there are other causes which need to investigated. Other causes may be colds, flu, allergies (called allergic postnasal drip), certain medications (including birth control pills and blood pressure medications), deviated nasal septum (abnormal placement of the wall that separates the two nostrils),
changing weather fronts, excess dryness in the air
certain foods (for example, spicy foods)
fumes from perfumes, cleaning products, smoke, or other irritants.

I wrote earlier for thinning of mucus -take lot of fluids and warm vapor inhalations to keep your nostrils open. You can also try ambroxol and antiallergic medicines.
I suggest you to have medicines after getting a look by an ENT specialist.

I think our discussion is getting prolonged and I am unable to add any value further to it. I wish you close the discussion and start as a new question posted preferably to an ENT specialist if you have pressing inquiries further.

Hope this helps.

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