Diphenhydramine: what is it and how can it help you sleep?

November 10, 2020 5 mins read
Diphenhydramine: what is it and how can it help you sleep?

Many people have discovered just how effective diphenhydramine can be in helping you fall asleep at night. Even when you’ve tried all the natural remedies to promote sleep – you’ve had your glass of warm milk, and you’ve counted all the sheep, you can still toss and turn at night.

At this point, you’re probably open to some assistance from a sleeping pill.

Pharmaceutical medications can be powerful in helping you deal with any symptoms and ailments that are affecting the overall quality of your life, including sleeplessness. But don’t take a medication if you don’t know what you are taking. Medications can have various side effects you need to be aware of.

Before you take diphenhydramine, learn what it is and how it can help you sleep.

What is diphenhydramine?

Diphenhydramine is an antihistamine that is used to treat symptoms of allergies, the common cold and hayfever. These symptoms include a blocked or runny nose, sneezing, itchy eyes, rash and itchy skin. It is also used at times to help induce sleep.

Many sleeping pills contain diphenhydramine to help induce sleep. You can find it in medications, such as:

  • Nytol Original
  • Nytol One-a-Night
  • Sleepeaze
  • Benylin Chesty Coughs
  • Covonia Night Time Formula
  • Histergan

This medication is mostly taken orally in pill, capsule or liquid form, but it can be taken intravenously, topically and by injecting it in the muscle.

How does diphenhydramine work?

Diphenhydramine works by blocking the reuptake of histamine, which is a natural substance your body creates when you have an allergic reaction to something.

Histamine is a neurotransmitter, a chemical messenger in your brain. Diphenhydramine blocks histamines in the synapses (the spaces between your nerve cells) and prevents them from being absorbed by the surrounding cells and causing symptoms like sneezing, itching and excess mucus.

High histamine levels can trigger insomnia, while low histamine levels can make you feel drowsy. If taking diphenhydramine does the trick and helps you fall asleep, it could indicate that you have high histamine levels.

What causes high histamine levels that interfere with sleep?

Histamines are produced in the body when you have an allergic reaction to something you ate, or something in the air or your environment. This could be anything from dust to grass, dogs, pollen and nuts.

Histamines are also commonly found in foods that are old or fermenting. They are found in low amounts in most foods but can be found in higher amounts in cured and smoked meats, aged cheese, dried fruits and fermented foods like yoghurt, sauerkraut, kimchi and alcohol.

If you are eating a lot of leftover food, you could be consuming high levels of histamines that might be interfering with your sleep. Consider the following precautions:

  • Freeze your leftovers as soon as possible to stop the production of histamines
  • Reduce your intake of cured meats and fermented foods
  • Don’t prepare foods too far in advance

Certain medications can cause high histamine levels, particularly those blocking diamine oxidase (DAO). DAO is an enzyme made in your kidneys, thymus and digestive tract that is responsible for regulating histamine levels. It breaks down excess histamines in the body.

What are the side effects of diphenhydramine?

Some side effects that may commonly occur with sleeping pills that contain diphenhydramine include:

  • Blurred vision
  • Confusion
  • Headaches
  • Digestive discomfort
  • Constipation
  • A dry nose or mouth
  • Dizziness
  • Drowsiness
  • Poor coordination
  • Somnolence
  • Sweating excessively
  • Increased pressure in the eyes (intraocular)

There are also more serious side effects you can experience, although these are rare. With diphenhydramine, serious side effects include:

  • Seizures
  • Anaphylaxis, which is a severe allergic reaction that causes difficulty breathing
  • Anaemia
  • Irregular heartbeat
  • Inner ear problems
  • Erectile dysfunction
  • Difficulty urinating
  • Toxic psychosis

If you experience any of these symptoms, stop taking the medication immediately and consult your doctor.

Is it safe to take diphenhydramine every night?

Because of the long list of potential side effects, you should not take diphenhydramine every night. If you do have chronic insomnia, it is best to speak to your doctor about alternative sleep aids.

Precautions to follow

There are some precautions and contraindications you need to be aware of.

  • Children under the age of two should not take diphenhydramine. It can cause side effects like rapid heart rate and convulsions and can potentially be fatal. Be cautious if you are giving it to children up to the age of six. Do so under medical guidance.
  • Older adults should also avoid diphenhydramine or be cautious when taking it because of possible side effects like blurred vision, confusion and poor coordination. It increases the chances of injury.
  • You should also be cautious if you have asthma, heart disease, hypertension, pneumonia, hyperthyroidism, an obstruction in your bladder or bowel and an enlarged prostate.

Natural sleep aids

Before taking sleeping pills or diphenhydramine, you could try a few natural remedies for sleep, such as:

  • Aromatherapy and massage
  • Yoga or light stretching before bed
  • Magnesium supplements
  • Herbal remedies like Valerian root and St John’s Wort
  • Guided sleep meditations
  • Exercising during the day

You can keep diphenhydramine in mind for the odd occasion that you struggle to sleep, but try not to make it a habit. If you are worried that taking it for one or two nights to help you sleep will damage your health, consider this:

Sleep deprivation has very negative side effects for your health, including an increased risk of accidents, hormonal imbalances, memory issues, increased diabetes risk, weight gain, a weakened immune system, high blood pressure and anxiety and depression.

Remember: taking a sleep aid to help you finally get the sleep you need could result in a much healthier you than if you didn’t get enough sleep.