Dizziness and nausea are both common symptoms that sometimes appear together. Many things can cause them, from allergies to certain medications. Keep reading to learn more about the possible causes of dizziness and nausea in different situations.

Postprandial hypotension

Postprandial hypotension refers to low blood pressure that happens after you eat. During digestion, the body reroutes extra blood to the stomach and small intestine. In some people, this causes blood pressure to drop everywhere else.

Other symptoms of postprandial hypotension include:

  • lightheadedness
  • nausea
  • fainting
  • chest pain
  • vision problems

Managing postprandial hypotension requires a series of lifestyle changes, such as drinking more water before meals or reducing your intake of carbohydrates.

Food allergies

Food allergies occur when your body’s immune system mistakes a certain food for something harmful. Food allergies can develop at any time. Most people with food allergies are allergic to peanuts, tree nuts, eggs, milk, fish, shellfish, wheat, or soy.

Eating something you’re allergic to can cause dizziness and nausea in addition to:

  • stomach cramps
  • rash or hives
  • shortness of breath
  • swelling of the tongue
  • coughing or wheezing
  • difficulty swallowing

Allergic reactions to food can range from mild to severe. While mild cases are usually treatable with over-the-counter antihistamines (Benadryl), more severe allergies may require a prescription steroid medication.

Acid reflux and GERD

Gastroesophageal reflux disease (GERD) is a type of long-lasting acid reflux. It happens when stomach acid flows up into your esophagus, which is the pipe connecting your mouth to your stomach.

Occasionally, stomach acid reaches the tubes leading to the inner ear. This may irritate the inner ear and cause dizziness in some people.

Other symptoms of GERD and acid reflux include:

  • heartburn after eating and at night
  • chest pain
  • cough
  • feeling of lump in throat
  • regurgitation of sour liquid

Acid reflux and GERD tend to respond well to over-the-counter medications, such as antacids, and dietary changes.

Food poisoning

Food poisoning happens when you eat something containing harmful pathogens, such as bacteria or fungi. While you might start noticing symptoms within a few hours of eating, it can sometimes take them days or even weeks to appear.

In addition to dizziness and nausea, food poisoning can also cause:

  • vomiting
  • watery or bloody diarrhea
  • stomach pain or cramps
  • fever

In addition, vomiting, diarrhea, and fever can all lead to dehydration, which can cause dizziness. If you have food poisoning, try to stay hydrated to avoid dizziness, which can also make nausea worse.


Dehydration can happen any time you lose more water than you’re taking in. This can happen when you don’t drink enough water. If you didn’t drink enough water the previous day, you might wake up dehydrated the next morning. This can cause dizziness and nausea.

Other symptoms of dehydration include:

  • headaches
  • dark-colored urine
  • decreased urination
  • extreme thirst
  • confusion
  • fatigue

If you’re regularly dizzy and nauseous in the morning, try drinking an extra glass or two of water a few hours before you go to bed. You can also keep a full glass of water on your nightstand that you can drink right when you wake up.

Low blood sugar

Low blood sugar happens when your body’s blood glucose level drops. It’s often a side effect of diabetes medications or not eating for long periods of time. Sometimes, your blood sugar can drop overnight while you’re sleeping, especially if you didn’t eat much the night before.

In addition to dizziness and nausea, low blood sugar also causes:

  • sweating
  • shaking
  • hunger
  • tingling sensation around the mouth
  • irritability
  • fatigue
  • pale or clammy skin

If you have diabetes, consider keeping glucose tablets or fruit juice on your nightstand for emergencies. You might also want to talk to your doctor about adjusting your insulin levels. If you have symptoms of low blood sugar and don’t have diabetes, try eating a small snack of carbohydrates when you wake up, such as a few crackers. Learn more about low blood sugar in the morning and how to prevent it.


Nausea and dizziness are common medication side effects. They’re especially common if you take medication in the morning on an empty stomach.

Some medications that can cause dizziness and nausea include:

If taking your medication in the morning makes you dizzy and nauseous, try eating a small snack, such as a piece of toast, before taking it. You can also try taking them in the afternoon or working with your doctor to adjust your dose.

Sleep apnea

Sleep apnea is a disorder that causes you to temporarily stop breathing while you sleep. This causes you to constantly wake up so you start breathing again. For many people with sleep apnea, this results in low-quality sleep and fatigue.

Not getting enough sleep, especially over a long period of time, can lead to dizziness and nausea.

Other symptoms of sleep apnea include:

  • loud snoring
  • abruptly waking up with shortness of breath
  • dry mouth and sore throat in the morning
  • headaches
  • excessive sleepiness
  • insomnia

Some cases of sleep apnea respond well to lifestyle changes. In other cases, you may need a CPAP machine or mouthguard.

Morning sickness

Morning sickness is a term used to describe symptoms of nausea and vomiting, sometimes accompanied by dizziness, during pregnancy. While it tends to happen earlier in the day, it can affect you any time. Experts aren’t sure why it happens or what makes some women more likely to have it.

There’s no standard treatment for morning sickness, but eating a bland diet or increasing your intake of vitamin B6 may help. You can also try these 14 recipes for morning sickness.

Sensitivity to odors

Many women find that their sense of smell changes during pregnancy. In fact, a more sensitive nose is often one of the first signs of pregnancy. It’s likely connected to an increase in certain hormones, including estrogen, during the pregnancy.

While you’re pregnant, the best option is to try to avoid things with odors that make you nauseated. Your usual sense of smell should return shortly after you give birth.

Dilated blood vessels

When you’re pregnant, there’s more blood circulation throughout your body. This can lead to blood pressure changes, which can cause dizziness and nausea.

Your body is also pumping more blood toward your baby, which means your brain doesn’t always get enough. If you feel dizzy, lie down with your feet elevated. This should help to increase blood flow to your brain.

Ectopic pregnancy

Usually, pregnancy begins when a fertilized egg attaches itself to the uterus. In ectopic pregnancies, the egg attaches to tissue outside the uterus. Ectopic pregnancies tend to happen inside the fallopian tubes, which carry eggs from the ovaries to the uterus.

Ectopic pregnancies often cause nausea and dizziness in addition to sharp pain and spotting. Left untreated, ectopic pregnancies can cause serious complications, including internal bleeding. Contact your doctor right away if you think you might have an ectopic pregnancy.


Migraines are a type of severe headache that usually produces a throbbing pain. They can also cause dizziness and nausea.

Other symptoms include:

  • feeling like there’s a tight band around the head
  • seeing flashing lights or spots (aura)
  • sensitivity to light and sound
  • fatigue

Experts aren’t sure about the exact cause of migraines or why some people tend to get them more than others. If you regularly get migraines, make an appointment with your doctor. They may prescribe a medication to help prevent future ones or minimize they’re symptoms. If you only get them occasionally, you can try this step-by-step guide for getting rid of a migraine.


A concussion is a mild traumatic brain injury that occurs when you receive a blow to the head or your head is violently shaken. When you get a concussion, your brain temporarily loses some functions. A headache, dizziness, and nausea are some of the main signs of a concussion.

Other concussion symptoms include:

  • confusion
  • vomiting
  • temporary memory problems

The symptoms of a concussion might night appear until several hours or days after the initial injury. While most people make a full recovery, it’s a good idea to see you doctor to check for any other damage.


Vertigo is the sudden feeling that everything around you is spinning or that you yourself are spinning. For many people, this also leads to nausea. One of the most common types is benign paroxysmal positional vertigo (BPPV). It occurs when certain head movements trigger episodes of severe dizziness. BPPV typically involves dizzy spells that come and go for several days.

Other symptoms include:

  • loss of balance
  • rapid or uncontrollable eye movements

You can manage vertigo symptoms by doing home exercises, such as the Epley maneuver or Brandt-Doroff exercises. If you continue to have symptoms, your doctor might prescribe medication, though most medications aren’t very effective for treating vertigo.


Meningitis is a condition involving inflammation of the tissues around the brain and spinal cord. While it’s usually caused by a virus, it can also be bacterial or fungal. Meningitis often causes a high fever, which can lead to some headache, dizziness, and nausea, especially if you aren’t eating much.

Other symptoms include:

  • stiff neck
  • confusion
  • seizures
  • no appetite or thirst
  • sensitivity to light
  • skin rash
  • fatigue or trouble waking up

If you think you have meningitis, make an appointment with your doctor as soon as possible or go to urgent care. While viral meningitis usually clears up on its own, bacterial meningitis can be fatal if left untreated. You doctor can order a lumbar puncture to help determine what kind of meningitis you have.

Dizziness and nausea are commons of many conditions, some mild and some serious. If your symptoms don’t go away after a few days, or you have repeated episodes of dizziness and nausea, make an appointment with your doctor to determine the underlying cause.