I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
Your doctor's plan for watchful waiting would not be considered as completely wrong. Though I would get an ENT specialist opinion and few investigative work up.
The causes of dizziness according to the decreasing incidence are;
1) Benign paroxysmal positional vertigo (BPPV) 20%
2) Vestibular 15%
3) Migraine and motion sensitivity 15%
4) Anxiety and depression 10%
5) Meniere's disease 7%
6) Cerebellar disease 6%
7) Transient ischemic attacks 5%
8) Orthostatic hypotension 4%
In your case I would have considered first four of the above causes as the culprit in your case. The diarrhea episode can be related as the virus or any other organism which caused intestinal infection may have affected the internal ear (vestibular infection).
Chronic dizziness associated with the floating, rocking and light headedness and is induced by eye movements (head being still) should be also investigated or correlated to anxiety and depression, if all the medical imaging, blood work and examination is negative. If you are on any medications, their side effects also should be ruled out for lightheadedness, as drugs are quite a common cause for this symptom. Dizziness may be provoked by only certain movements, such as standing up after lying down for at least 10 minutes in orthostatic hypotension, or may occur after vertical or oblique head movements, such as lying down, turning over in bed, or sitting up in benign paroxysmal positional vertigo (BPPV). Simply moving the eyes with the head stationary causes dizziness and there is no eye movement disorder (ocular misalignment or an internuclear ophthalmoparesis), then dizziness is likely to be the result of anxiety. When dizziness occurs without provocation (spontaneous) and is vestibular (ear disorder) in origin, it frequently is exacerbated by head movements.
Internal ear disease vertigo is termed true vertigo in which one feels rotational movement of self or the surroundings. The false vertigo or nonvertigo has feeling of light-headedness, unsteadiness, motion intolerance, imbalance, etc. You need to consult first an ENT specialist to exclude the diseases of internal ear. They will perform some clinical tests (vestibular diagnostic tests) to establish the cause. Often, dizziness can be a multisensory disorder due to any combination of peripheral neuropathy, visual impairment, and musculoskeletal disease. Many patients who have thyroid dysfunction can present with dizziness as an initial complaint. In individuals who have migraine, dizziness and vertigo can occur as part of the aura or separately. Spells usually last approximately an hour but can last several hours or days in patients who have severe symptoms. Most patients who have migraines have a long history of recurring symptoms. So that too should be re-assessed as a cause since you have a history of migraine.
If you have another episode of significant dizziness, your doctor should also get an MRI with gadolinium contrast.
Your primary care physician should refer your to a neurologist, cardiologist and ENT specialist for evaluation if the dizziness increase or another acute attack occur, as the causes can be divided on the system, which is involved;
1) Inner ear or internal ear disease
2) Central nervous system
3) Cardiovascular, or
4) Systemic diseases
That should be able to conclude for the diagnosis.
Acute dizziness and vertigo is usually managed with;
1) vestibular suppressants,
2) antiviral medication,
3) antiemetic medications
Vestibular rehabilitation can help which is an exercise program. Please read this resource for the exercises;
Exercises are graded in difficulty based on velocity of head and object motion and by progression of body positioning from sitting to standing to walking. The exercises are graded in difficulty by narrowing the base of support, making the surface uneven, or changing the surface from firm to soft. Varied walking exercises are graded in difficulty by changing direction, requiring performance with the eyes closed, increasing speed of ambulation, walking on soft surfaces, or navigating stairs. An aerobic exercise home program progressively increasing the time, speed, or distance that the patient could tolerate also can be initiated. But all of these may need supervision of a doctor if vertigo is severe.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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