How Long Should I Diffuse Essential Oils?

by Bella Martinez June 02, 2021

How Long Should I Diffuse Essential Oils?

Diffusion is one of the most prevalent ways to enjoy essential oils and obtain their natural benefits. As essential oil lovers ourselves, we admit to getting carried away with diffusing. We love switching on the diffuser in the morning, noon and night to help alleviate stress, create an aromatic atmosphere, keep germs at bay — you name it. 

 But is there a time limit you should put on your diffuser? Don’t miss this commonly overlooked essential oil safety tip.

What Can Happen If You Diffuse For A Long Period Of Time?

Leaving an active aroma diffuser on for over an hour continuously is often considered diffusing for too long. Here’s what can happen if you diffuse for longer than an hour. 


Have you ever used an essential oil continuously, then noticed it didn’t work as well as it once had or that you’ve become nose-blind? It may be that your body has adapted to that oil, rendering it less effective than when you had first used it. 

 Most people are familiar with the way you can build up a tolerance to alcohol and medications. This is known as habituation, and it can occur if you use the same substance too often.

 Luckily, you can avoid habituation, also known as “olfactory fatigue,”  by alternating the essential oils you use and by reducing the duration you use them. Along with limiting topical use of essential oils, restricting your diffuser’s “on” setting is another way to prevent your EO tolerance. Try switching up your oils once every 1- 2 months to ensure they work each and every time you use them. 

Safety Issues

Along with essential oil habituation, there are safety issues at play when it comes to prolonged essential oil exposure. 

  • One study showed that after an hour of being exposed to essential oils, volunteers experienced increased heart rates, which researchers concluded could be harmful to heart health. However, the same study revealed 15-60 minutes of inhaling essential oils resulted in deeper relaxation and decreased heart rate. 

 Overexposure to diffusion can also lead to headaches, dizziness, nausea, brain fog and more. Thus, the importance of limiting your diffuser time can’t be understated.

How Long Should I Diffuse?

So how long should you diffuse to get optimum effects? That depends on the people (or pets) you’re diffusing around and what type of diffuser you’re using. 

Types Of Essential Oil Diffusers

There are two types of diffusers: active diffusers and passive diffusers. 

Active Diffusers

These diffusers use a stimulus such as electricity, ultrasonic vibrations, airflow, etc. to emit essential oils. Active diffusers offer an intense aroma output and therefore should be switched on less frequently, or put on an intermittent diffusion setting. At Edens Garden, the following diffusers are considered active:

*Note, though it doesn’t require a stimulus to diffuse, the Personal Pocket Inhaler delivers the same amount of aroma intensity as a nebulizing diffuser in a few, short bursts. 


Passive Diffusers

A passive essential oil diffuser naturally emits pure essential oil without any help from a stimulus. These diffusers generally offer a less intense aroma output and can be used to diffuse essential oils continuously. Just replace the oil as needed. We offer the following passive diffusers:

Diffusing Essential Oils Around Different Individuals

Healthy Adults

Older children and healthy adults may get the most out of their favorite essential oil after 30- 60 minutes of continuous inhalation using an electric diffuser. They can also enjoy continuous diffusion using a passive aromatherapy diffuser. 


The Elderly & Those With Compromised Immune Systems

The elderly and those with health problems or compromised immune systems may require less diffusion time to see effective results with essential oils. Try using an active diffuser for up to 30 minutes, or using a passive diffuser continuously.



Young children need considerably less inhalation–only about 15- 30 minutes of active diffusion or continuous passive diffusion. 


Babies & Pets

It’s generally not recommended that you use an active diffuser around babies or pets. A baby or pet-safe essential oil can be used in a passive diffuser.


What about topical application? 

Diffusion may be the most straightforward approach to using essential oils, but using them topically can also offer a range of therapeutic benefits. In order to apply essential oils safely to the skin you'll need to properly dilute them with a carrier oil. To read more about dilute read our Ask An Aromatherapist article," How To Read A Dilution Chart." 

Grab The Essentials Here:

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Edens Garden

July 19, 2023 at 8:39 am

Hi Connie! You can read safety tips about diffusing around pets here:


July 19, 2023 at 8:38 am

Since I have many, many houseplants, will diffusing affect them in any way?

Jan Hodge

June 4, 2021 at 9:07 am

That’s a little like saying “Why do you sell undiluted oils if you’re supposed to dilute them?” The responsibility is on the user to learn how to use the product. I haven’t personally been using essential oils very long but learned early on through EG not to diffuse too long and have found that most people know this safety tip.

Edens Garden

June 3, 2021 at 8:31 am

Hi Kathleen! We would suggest diffusing 30 minutes before bed or using a passive diffuser next to your bedside. You may also diffuse 1-2 drops in 100 ml of water using an active diffuser through the night.


June 3, 2021 at 8:11 am

Why do you publish such an article and then sell diffusers that run continuously for 2 – 3 hours and then one that runs continually, but intermittently for 8 hours? Do you consider yourselves jeopardizing someone’s health if someone has not read your article yet buys your diffuser? Does not seem to be good corporate citizenship.


June 3, 2021 at 8:10 am

This article is very timely for me in particular. I am a guilty diffuser, as I was just thinking, I wonder if I am nose blind. I use my diffuser several hours daily. I will back off the hours and switch the oils.

Kathleen Steffler

June 3, 2021 at 8:10 am

I use a diffuser with the Good Night essential oil I get from your website. I use it every night. After reading this article I’m wondering how I should follow your recommendations.

Edens Garden

June 3, 2021 at 8:03 am

Thank you, Jeannie! We will look into this. In the meantime, we recommend copying and pasting the link into your preferred search engine.

Edens Garden

June 3, 2021 at 8:03 am

Hi Donna! It depends on the type of diffuser you’re using and how much oil, but we would not suggest using an active diffuser at max oil capacity all night. Adverse effects can occur immediately or over time.

Jeannie warner

June 2, 2021 at 9:06 am

Your above links said,Page Not Found.


June 2, 2021 at 9:06 am

So does that mean I shouldn’t be leaving my diffuser on overnight? I have been using a diffuser at bedtime for over a year. It really helps me sleep better.