It’s not unusual to occasionally experiencenauseaorlightheadedness; both are common and usually have nonserious causes.
It also explains when nausea and lightheadedness are signs of a medical emergency needing immediate care.
Nausea may precedevomitingor occur on its own.
FG Trade / Getty Images
Lightheadednessis another term forpresyncope, meaning the sensations you have before fainting (syncope).
Symptoms of presyncope can vary but may include:
What Causes Nausea and Lightheadedness?
Many conditions can cause nausea and lightheadedness.
Most are not serious, but others are potentially life-threatening.
Hypoglycemia
Hypoglycemiais the medical term for low blood sugar (glucose).
Glucose is the body’s main energy source.
When levels fall too low, the body is less able to function normally.
Hypoglycemia is common among people with uncontrolled diabetes.
Migraine
Migraineis a common neurological (brain-related) disorder that causes recurrent headaches, sometimes severe.
The headaches are often described as throbbing or pounding and usually affect one side of the head.
Nausea is common, which can precede or accompany a migraine attack.
As with all migraines, nausea and vomiting are common with vestibular migraine.
In some cases, you may experience theseprodromal(preceding) symptoms but not fainting.
Vasovagal syncope happens when the part of thenervous systemthat regulates heart rate and blood pressure suddenly malfunctions.
A focal seizure may occur on its own or lead to a classicgeneralized seizure.
Medications
Any number of medications can cause nausea.
Some also directly or indirectly affect blood pressure, triggering presyncope.
It triggers when a colorless, odorless, tasteless gas called carbon monoxide builds up in your bloodstream.
Carbon monoxide is produced by burning gasoline, wood, propane, charcoal, or other fuel.
Other symptoms include blurred vision, shortness of breath, confusion, and vomiting.
If not removed from the source of the toxic fume, a person can pass out and die.
The six classicsymptoms of a heart attackare:
Not all heart attacks are readily recognizable.
In some cases, you may only experience signs like nausea and lightheadedness.
These are referred to assilent heart attacks.
Brain Tumors
A less likely cause of nausea and lightheadedness is abrain tumor.
These includemalignant(cancerous) tumors andbenign(noncancerous) ones.
Both produce symptoms that vary based on the tumor’s size, key in, and location.
A headache is the most common sign.
How to Treat Nausea and Lightheadedness
The treatment of nausea and lightheadedness varies by the cause.
You may be able to treat these symptomatically with home remedies, diet, medications, and mind-body therapies.
On its own, nausea is a condition that can usually be managed in children.
Certainly, for parents and caregivers, fainting or near-fainting episodes can be alarming.
In most cases, the cause of presyncope in children will not be serious.
However, frequent lightheadedness should not be ignored.
On rare occasions, it may be a sign of an undiagnosed heart condition or epilepsy.
How to Prevent Nausea and Lightheadedness
There is often no way to completely avoid nausea and lightheadedness.
They can happen after doing something simple as watching an IMAX movie or exerting yourself more than you intended.
One rare but potentially life-threatening cause of nausea and lightheadedness isanaphylaxis.
Summary
Individually, there are many possible causes of nausea and lightheadedness.
Less common causes include epilepsy, brain tumors, heart attacks, anaphylaxis, and carbon monoxide poisoning.
Fortunately, most cases are not serious and tend to pass without further incident.
Even so, it’s important to let a healthcare provider know about it at your next appointment.
If nausea and lightheadedness occur repeatedly, schedule an appointment as soon as possible.
To aid with the diagnosis, bring information about when and where the episodes occurred.
Frequently Asked Questions
Lightheadedness is the feeling that you are about to faint.
Dizziness is when you feel unbalanced or feel the room spinning.
Dizziness often accompanies lightheadedness.
If you feel faint while standing, this is calledorthostatic hypotension.
The two conditions can co-occur and are sometimes mistaken for the other.
A historical analysis of changing views.Auton Neurosci.
2019;140(24):e931-e938.
doi:10.1161/CIR.0000000000000730
American Diabetes Association.6.
Glycemic targets: standards of medical care in diabetes2022.Diabetes Care.
2022;45(Supplement 1):S83S96.
2013;98(10):39A-40A.
doi:10.1210/jc.2013-v98i10-39A
Weatherall MW.The diagnosis and treatment of chronic migraine.Ther Adv Chronic Dis.
2015;5(6):a022426.
Merck & Co.Cozaar (losartan potassium) label.
Pfizer Pharmaceutical.Norvasc (amlodipine besylate) label.
Abbott Pharmaceutical.Tricor (fenofibrate) label.
Sandoz Pharmaceutical.Elavil (amitriptyline) label.
Centers for Disease Control and Prevention.Carbon monoxide poisoning basics.
National Heart, Lung, and Blood Institute.Heart attack: what is a heart attack?
Kozak, Robert.Silent heart attacks all too common, and often overlooked.
2019;99(1):17-24.
Epilepsy Foundation.Alcohol as a seizure trigger.
2015;91(9):617-624.
Fischer D, Vander Leek TK, Ellis AK, Kim H.Anaphylaxis.Allergy Asthma Clin Immunol.
2018;14(S2):54. doi:10.1186/s13223-018-0283-4
Centers for Disease Control and Prevention.Recognizing and responding to anaphylaxis.
National Library of Medicine.Chapter 212: dizziness.
In:Clinical Methods: The History, Physical, and Laboratory Examinations.3rd ed.
Nwazue VC, Raj SR.Confounders of vasovagal syncope: orthostatic hypotension.Cardiol Clin.
2013;31(1):89100. doi:10.1016/j.ccl.2012.09.003
Saklani P, Krahn A, Klein G.Syncope.Circulation.
