Why Do You Feel Sicker at Night When You Have a Cold or Flu? (2023)

When you’re sick, you might notice that you feel much worse at night. Bodily rhythms, hormones, and chemistry can affect the severity of your symptoms. There may also simply be fewer distractions at night to take your mind off your symptoms.

Read on to learn some of the possible reasons you might feel worse at night when you’re sick, how you can prepare yourself at night to relieve some of your symptoms, and when you should get medical attention.

Here are some common reasons that symptoms seem more severe at night.

Hormones and circadian rhythm

Your circadian rhythm is like an internal clock that helps control the changes that happen in your body throughout the day. Factors that can affect your circadian rhythm include:

• how much sleep you get
• the amount of light you’re exposed to throughout the day (both natural and artificial)
• how much you exercise
• your levels of stress from physical, mental, or emotional factors

Your circadian rhythm is also tied to variations in hormone levels throughout the day. And many different hormones in your body rise and fall frequently in response to your circadian rhythm, including:

• cortisol
• estrogen and progesterone
• hormones that regulate hunger, such as insulin, leptin, and ghrelin
• melatonin
• thyroid hormones
• growth hormones

Cortisol levels can rise and fall drastically throughout the day in response to stress, lack of sleep, your immune system, and other factors. Cortisol is involved in keeping many other hormones balanced. An imbalance in cortisol can cause other hormones to become imbalanced and make you feel worse at night.

Estrogen and progesterone, sex hormones that are involved in many processes like menstruation and pregnancy, may peak during the day and fall during the night. When hormone levels fall at night, they can result in feelings of irritation or anxiety. When you’re sick, this extra stress on your body can make your symptoms feel worse.

Body positioning

Your body position during the night can also affect the way you feel when you’re sick. Gravity can act differently on different processes or organs in your body when you sit, lie down, or move from side to side in bed.

For example, you may feel worse when you lie down to sleep because mucus buildup from a cold or the flu can cause congestion or pressure in your sinuses that result in a headache or sinus pain. If you’re a side sleeper, you might feel most of this pain or pressure on one side of your head.

Your body position can also put pressure on areas of your body that may be affected by your illness. Let’s say you have pain in your left hip. If you’re used to sleeping on your left side, the extra pressure and compression on that hip caused by your bed can make the pain feel worse, even after you’ve changed positions.

Fewer distractions

During the day, many distractions can occupy your mind, such as work, family, and entertainment. This may help draw your attention away from your symptoms when you’re sick and make them feel less severe.

When you’re up and awake, you’re also usually much more willing to move around in order to treat and manage your symptoms. This can include blowing your nose, taking medication, applying cold compresses or heating pads, and so on.

But when you’re trying to sleep, you may notice a particular pain, discomfort, or other symptom more than you normally would. And if your symptoms cause you to wake up and move around to do something about it, the combination of interrupted sleep and symptoms can make you feel especially miserable.

You might also feel more anxious at night as less occupies your mind. Anxiety can make your symptoms feel more acute and put additional stress on your body, which also throws your hormones out of balance.

Cortisol is closely linked to your immune system function. Cortisol is higher during the day, and these higher levels suppress your immune activity to a large degree. When cortisol levels go down at night, your immune system is more active in fighting illness or infection.

This is why fevers spike at night. It’s a sign that inflammation processes are responding to the presence of bacteria, viruses, or other infectious matter in your body and your immune system is actively fighting against an illness.

Your body temperature also fluctuates throughout the day. It’s typically at its highest in the early evening. These natural changes in temperature may seem more noticeable when your body’s hotter from a fever and active infection.

Some COVID-19 symptoms can be worse at night for many of the reasons we’ve discussed above.

Coughing or respiratory symptoms that are common in COVID-19 infections may be made worse by congestion caused by mucus buildup in your lungs and sinuses.

Your immune system may also be working harder to fight off the viral infection at night when cortisol levels dip. This can make COVID-19 symptoms feel worse, too.

COVID-19 has also been linked to insomnia. Being unable to sleep at night can make your symptoms feel more uncomfortable. And your lack of sleep can throw your hormones off balance and worsen your symptoms.

You may not be able to make your symptoms go away until you’re recovered from your illness, but there’s plenty you can do to help reduce the severity of your symptoms.

Stay hydrated

Drinking enough water each day keeps you hydrated and supports your overall health as well as your immune system function.

Staying hydrated can also make sure you replenish the body fluids and electrolytes you lose when you sweat during a fever.

The exact amount of water you need to stay hydrated is different for every person. But try to drink at least 64 ounces of water throughout the day (about eight 8-ounce glasses). Drink a little more if you’re drinking caffeine or alcohol, live in a hot or dry climate, or are exercising at all while you’re sick.

Get more sleep during the day

Make sure you’re getting enough sleep to support your immune system while it’s fighting off an infection.

Cortisol levels are lower when you’re sleeping, so sleep supports a healthy and active immune system that’s important while you’re sick. A typical 7 to 9 hours of sleep might not be enough to allow you to heal quickly.

Sleep also allows your body to rest and keep your hormones in balance.

Take supplements

Some vitamins, minerals, and herbs can help you treat symptoms or help reduce the impact that different causes can have on your body at night.

Some supplements boost immune function and may help you feel better at night when you’re sick. A 2018 study suggested that the following supplements may help treat the common cold alongside other medical treatments:

• vitamin C
• vitamin D
• zinc
• Echinacea

Taking melatonin may also help normalize your sleep cycle and balance other hormones that may become imbalanced from illness or a lack of sleep. Evidence is mixed on how effective melatonin is, but you can ask your doctor about how it can help with insomnia or other sleep issues in combination with other treatments and lifestyle changes.

Have supplies ready

Maintaining a comfortable sleeping environment and limiting how often you need to get out of bed can help reduce the impact that your symptoms have on you while you’re trying to sleep.

Try to keep some of the basic supplies you need close to you, including:

• tissues to clear mucus
• water to stay hydrated
• cough drops or cough medication to reduce coughing episodes
• medications and treatments for your symptoms
• fan or humidifier to adjust your environment throughout the night
• remotes for electronic devices, such as a TV, that you’ll want to turn off without leaving your bed

You may notice that your symptoms are only present at night but go away during the day almost entirely. This could mean that your sleeping environment might be the cause of your symptoms.

Common indoor allergens like dust or other air pollution can cause symptoms like:

• stuffiness
• coughing
• sneezing
• runny nose

Indoor humidity levels can also dry you out or make mucus drain more noticeably. Try an air purifier, humidifier, or dehumidifier to help reduce these triggers.

Your sleeping environment may be too cold or too hot at night, especially if you’re running a fan, air conditioner, or heater. Try to adjust your HVAC system or sheets and blankets so that the temperature stays consistent and you don’t have to shift or change positions too often.

Some homes may also have mold, chemicals, or housing materials that can make you feel sick.

If your sleeping environment has any of these triggers in high levels in comparison to the rest of your living space, you might notice stronger reactions to them when you’re trying to sleep. Consider having your home inspected for mold or other environmental triggers.

You may be able to treat most symptoms with a combination of rest, hydration, medication, and some changes to your environment.

But contact a doctor as soon as possible if you’re experiencing:

• trouble breathing
• constant pain that doesn’t get better with lifestyle changes, treatments, or time
• feeling disoriented or confused
• trouble waking up or staying awake without significant effort
• unusual colors in your lips or face, such as bluish tints from a lack of oxygen

Some illnesses may make you feel worse at night for numerous reasons, including changes in your hormone levels, immune system activity, and body position.

Making changes to your lifestyle and environment can help reduce the strain of your symptoms on your body at night. But contact a doctor if you’ve tried to make adjustments and your symptoms aren’t getting better.