Can rosemary oil cause hair loss?

Rosemary oil is one of the most popular oils used by many for hair growth. But can rosemary oil cause hair loss? Let’s find out.
When it comes to hair health, coconut oil, onion oil and almond oil are some of the popular choices. But if you specifically look for hair loss solution, many people will guide you to use rosemary oil. It is not just a social media trend, as there is evidence that shows the oil derived from Rosmarinus officinalis shrub can help to promote hair growth. While it has gained attention for its potential benefits for hair, there are also side effects. In fact, if it is not applied in a proper manner, it may lead to hair loss. So, can rosemary oil cause hair loss?
What are the benefits of rosemary oil for hair?
The essential oil offers the following benefits for hair:
- Promotes hair growth: “This type of oil can promote hair growth by improving blood circulation to the scalp, which can nourish hair follicles,” says aesthetic physician and cosmetologist Dr Karuna Malhotra. A 2015 study, published in Skinmed, showed that people who used rosemary oil for six months, experienced a significant increase in hair count.
- Reduces dandruff: “This oil’s antimicrobial properties can help combat dandruff and maintain a healthy scalp,” says the expert. Rosemary contains rosmarinic acid, carnosic acid and carnosol, which offer antimicrobial anti-inflammatory, antioxidant effects, as per research published in the Iranian Journal Of Basic Medical Sciences in 2020. “Its anti-inflammatory properties can soothe an itchy or irritated scalp, reducing flakiness over time,” says the expert.

Can rosemary oil cause hair loss?
While this particular oil is known for its hair growth benefit, you may ask, “Can rosemary oil cause hair loss?” This can be due to the following reasons:
1. Undiluted application
The essential oil is highly concentrated, and applying it directly to the scalp without mixing it with a carrier oil can cause irritation. “This may lead to redness, itching and scalp inflammation. A damaged scalp can weaken hair follicles, leading to hair loss,” says the expert.
2. Overuse and oil build-up
Can rosemary oil cause hair loss? The answer to this question is connected to overuse. Using it too frequently such as daily or in excessive amounts can lead to product build-up on the scalp. “This may clog hair follicles, disrupt natural oil production, and cause dryness or excessive greasiness, both of which can contribute to hair weakening and hair loss,” says Dr Malhotra.
3. Allergic reactions
Some people may have an allergic reaction to this oil after application. One of the symptoms of an allergic reaction include itching, which can make you scratch frequently. “Scratching your scalp frequently can damage your hair follicles. This can obstruct natural hair growth, and lead to hair loss,” says the expert.
4. Weak hair falls out
Can rosemary oil cause hair loss? It can if you have just started using it. Initially, some people may experience an increase in hair shedding. “This is because dormant or weak hair may fall out as circulation improves and new, healthier hair begins to grow. This temporary shedding can be mistaken for hair loss, but the problem usually gets resolved within a few weeks,” says the expert.
5. Poor scalp health
If you have an underlying scalp condition such as seborrheic dermatitis, psoriasis, or fungal infections, rosemary oil may not work effectively. “It can even worsen symptoms of these scalp problems, and may even lead to hair loss,” says Dr Malhotra. In such cases, consulting a dermatologist is crucial before using any essential oil, including rosemary oil.
Can rosemary oil cause hair loss? Know how to use it correctly
Can rosemary oil cause hair loss? Not if you use it in the right way. Follow these steps to prevent hair loss while using this essential oil:
- Dilution: Always dilute this oil with a carrier oil before applying it for making your hair strong. Carrier oils like coconut oil, argan oil and sunflower oil can help to use rosemary oil safely, as per research published in Evidence-Based Complementary and Alternative Medicine in 2019. “A common ratio is 3 to 5 drops of rosemary oil per tablespoon of the carrier oil of your choice,” says the expert.
- Scalp massage: Gently massage the diluted mixture into your scalp, and leave it on for at least half an hour before washing it out.
- Consistency: Use this treatment 1 to 2 times a week instead of making it a daily habit.

Other side effects of rosemary oil
Can rosemary oil cause hair loss? It may. Here are some more possible adverse reactions of using it.
- Skin irritation: It is a potent essential oil, and when applied without diluting it with a carrier oil, it can cause irritation, redness, itching, or a burning sensation on the scalp.
- Photosensitivity: Essential oils, including rosemary oil, can sometimes increase sensitivity to sunlight. “Applying this oil to your scalp or skin and then exposing it to direct sunlight can increase the risk of sunburn and redness,” says the expert.
- Interference with medications: Since rosemary oil improves circulation, it may interact with blood-thinning medications, increasing the risk of bleeding. “People taking anticoagulants or those with bleeding disorders should consult a doctor before using rosemary oil on their scalp or skin,” suggests the expert.
So coming back to the question, “Can rosemary oil cause hair loss?”, we can safely say that while it is an effective remedy for hair health, it needs to be used carefully. Diluting it properly, avoiding excessive use, and being mindful of your sensitivities can help you enjoy its benefits while minimising side effects like hair loss.
Related FAQs
Can you leave rosemary oil in hair daily?
Daily application of rosemary oil may lead to scalp irritation or oil buildup. It’s best to use it 1 to 2 times a week. See how your scalp reacts then use it.
How to dilute rosemary oil?
Mix 3-5 drops of rosemary essential oil with one tablespoon of a carrier oil. You can also add a few drops of the oil to your regular shampoo or conditioner. Ensure it’s well-mixed before using it.