Brief Answer:
You are probably suffering from Eustachian tube blockage

Detailed Answer:
Hi XXXX,thank you for posting your query on health care magic.

Looking at your symptoms, the ear blockage which you are suffering due to cold, is probably due to Eustachian tube blockage. Eustachian tube is a tube connecting the middle ear and nose and is responsible for equalization of middle ear pressure with the outer atmospheric pressure.

In case of blockage of the tube, the middle ear pressure is not able to remain equal to outer atmospheric pressure resulting in negative middle ear pressure. This condition gets aggravated in situations where there is more change in outer atmospheric pressure like flying. The negative middle ear pressure may result in fluid collection in the middle ear.

You have taken Benadryl. It contains Diphenhydramine. It can be used to treat the nasal allergic symptoms .

You may also find relief by taking Oral Decongestant (like containing Phenylephrine) if you are not suffering from hypertension. Nasal Decongestant Drops(like Oxymetazoline), Steroid nasal spray(like containing Mometasone) and a Mucolytic (like Ambroxol) along with Benadryl [Please obtain the necessary prescription from your local physician].

Also Do steam inhalation three times a day(steam helps in decongestion of nose and may remove the blockage in eustachian tube). Avoid cold and very sweet food(as they increase mucus production). Avoid dust, smoke and other pollutants (as they may increase the Cold).

Drink lots of fluids(warm) as they help in breakage of mucus secretions collected due to cold. Hot tea with ginger,honey and lemon might also give you relief.

Hope this answers your question.I would be happy to answer you if you have any follow-up questions.

Get well soon.

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