Orthostatic Hypotension: This condition is characterized by a sudden drop in blood pressure when standing up, which can lead to dizziness. It is a common cause of transient dizziness, especially in the morning when getting out of bed.

Dehydration: Waking up dehydrated can cause dizziness due to decreased blood volume and subsequent drop in blood pressure.
Sleep Disorders: Disorders like sleep apnea or insomnia can lead to dizziness upon waking due to poor quality sleep or decreased oxygen saturation during sleep.
Vestibular Migraine: Although more commonly associated with headache, vestibular migraines can cause dizziness without headache, and symptoms can be triggered by positional changes.

Cardiac Arrhythmias: Conditions like atrial fibrillation or other arrhythmias can cause dizziness due to inadequate cardiac output. Missing these diagnoses can be life-threatening.
Hypoglycemia: Low blood sugar, especially in diabetic patients, can cause dizziness and is a medical emergency if not promptly treated.
Postural Orthostatic Tachycardia Syndrome (POTS): Characterized by an excessive heart rate increase upon standing, POTS can cause dizziness, among other symptoms, and requires specific management.

Multiple System Atrophy (MSA): A rare neurodegenerative disorder that can cause orthostatic hypotension leading to dizziness upon standing.
Adrenal Insufficiency: A condition where the adrenal glands do not produce adequate amounts of hormones, which can lead to orthostatic hypotension and dizziness.
Autonomic Dysfunction: Various conditions affecting the autonomic nervous system can lead to orthostatic intolerance and dizziness, including pure autonomic failure.