Hello. Thank you for writing to us.

It does look like most of the serious conditions have been ruled out in order to diagnose the cause of your lightheadedness/vertigo/dizziness. There could be a few more conditions that could cause lightheadedness. Let me list them for you, so you can relate to them or even take them up with your primary doctor. They are:
-Hypotension (a drop in blood pressure results in less blood reaching the brain, thus lightheadedness)
-Orthostatic hypotension: a more specific type of hypotension seen with change in posture (i.e. From a supine to standing position, etc.)
-Dehydration (you could try consuming more fluids during lightheadedness)
-Respiratory conditions (as you have been diagnosed with asthma, if your asthma is not controlled there could be situations where there is less amount of oxygen reaching the brain, which can also cause lightheadedness)
-Hypoglycemia (low blood sugar; hoping this has been ruled out during the blood work; I also hope your blood sugar levels were checked during the lightheadedness and not when you were asymptomatic i.e. without any symptoms)
-Panic attack (do you also experience fear, breathe rapidly, etc. along with the lightheadedness; these could mean you are having a panic attack)
-Stress (this has also found to present with lightheadedness in many individuals)
-Drugs: antibiotics, antihistamine drugs (used to treat allergic reactions), anti-depressants, anti-anxiety drugs, etc.
-Migraines [a condition which has symptoms of a severe headache, black/white spots in vision, photophobia (irritation from light during the attack), irritation by sound]
-Labyrinthitis: condition in which there is inflammation and irritation of the inner ear (has lightheadedness as a symptom)
-Vertigo can sometimes be the main condition and not just a symptom (this can be treated with anti-vertigo drugs)
-Vasovagal syncope: A nerve called the vagus nerve is over-stimulated which results in dilation of the body's blood vessels. This in turn causes the heart to slow down and thus a lesser amount of blood is pumped to the brain, resulting in lightheadedness
-Thyroid disorders: (hypo and hyperthyroidism also present with lightheadedness)
-Addisons disease: Symptom of lightheadedness (diagnosed by low cortisol levels)
-Meniere's disease: disorder of the inner ear that can cause vertigo (lightheadedness)

I understand that the list is long, but I have only listed them for your information, so you could refer to it and narrow down your search.

Your symptoms of post-nasal drip, ears popping, red throat, etc. match a condition requiring attention from an ENT (ear, nose, throat) specialist; before deciding whether your lightheadedness is related to this condition or has a totally different cause altogether.

I hope this information helps. Please feel free to write back to me with any further clarifications and I shall try my best to help you. As I cannot physically examine you, I can only suggest what is best from my knowledge. Also, please discuss the possibility of being treated with anti-vertigo medication (betahistine), with your doctor.

Best wishes.

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Hi,

Thank you for your follow up query.

The symptom of yours could be a condition called sleep paralysis. It is the transient inability to move or speak during sleep transitions. Sometimes, accompanied by hallucinations (rare).
People experiencing this describe it as the feeling of someone sitting on them. In olden times, this was even associated with the myth of ghosts or spirits.
Sleep paralysis occurs when you are first falling asleep (hypnagogic) or when you are waking up (hypnopompic).

Other symptoms:
-people try to scream out for help, but resulting voice is very soft
-suffocation or breathlessness like feeling
-hallucinations (although rare, are in visual, auditory and/or tactile form)

Occurs in whom?
-Lack of sleep
-Change in sleep cycle
-Stress (most common) or bipolar disorder
-Sleeping on back
-Substance abuse or use of other medication
-Sleep disorders like narcolepsy or nighttime leg cramps

From my experience, I have almost always seen young women complaining of these symptoms, and it is usually associated to stress. Please visit your doctor if you need help with this. I hope I have provided you with information you were looking for. Feel free to write back to me.

Take care

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Hello, thank you for your response.

Yes, individuals that suffer from sleep paralysis also experience chest tightness resulting in breathlessness and even trembling due to the fear of the occurring symptoms, as I have listed above, but this is only if you experience this during your sleep and wake up with these.

If you experience this even through the day, then you could go through a few causes that I have listed in my first response that can cause a similar presentation that you are experiencing. If you feel any particular cause could be the one causing you trouble, write back to me and I would gladly explain things more elaborately. You could also discuss the possibilities with your doctor.

Do write back to me for any further clarifications.
Best wishes.

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