Report on Rosemary Side Effects and Usage


Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using rosemary (Rosmarinus officinalis). These are referred to as drug/herb interactions.

Warning 1 – Contraindications: Pregnancy, high blood pressure, epilepsy, ulcers, Crohn’s disease, and ulcerative colitis. Rosemary oil can be toxic if ingested, and should never be taken orally.

Warning 2 – Anticoagulants: Rosemary may increase bleeding when used concurrently with anticoagulants. Be sure to consult your doctor if you are taking any blood-thinning drugs such as Plavix, Coumadin, or Aspirin.

Warning 3 – ACE inhibitors: Rosemary may interfere with the actions of ACE inhibitors such as Capoten, Monopril, Vasotec, Zestril, and other high blood pressure medications.

Warning 4 – Anemia: Research published in the “American Journal of Clinical Nutrition” (March 2001) revealed a link between rosemary’s phenolic compounds and a decrease in the absorption of dietary iron. Therefore, it’s not recommended that anyone with iron-deficiency anemia ingest rosemary oil. Topical preparations should be safe.

Warning 5 – Antidiabetics: Because rosemary affects blood sugar levels it could interfere with any drug taken to control diabetes.

Warning 6 – Antispasmodics: Rosemary might make seizure disorders worse. Experts recommend avoiding concurrent use.

Warning 7 – Diuretics: The University of Maryland Medical Center cautions that if rosemary causes the body to lose too much water, people taking lithium may see levels of the drug build up to toxic levels. Rosemary-induced water loss also can adversely affect patients taking furosemide (Lasix) or hydrocholorothiazide and the absorption of those drugs.

Used as a natural health remedy: Rosemary is used internally for the following benefits and conditions:

  • Antioxidant properties
  • Cough
  • Dandruff
  • Digestion problems
  • Intestinal gas (flatulence)
  • Gallbladder complaints
  • Get rid of head lice
  • Gout
  • Hair loss (alopecia)
  • Headache
  • Heartburn
  • High blood pressure
  • Improve memory
  • Increase menstrual flow
  • Indigestion
  • Liver complaints
  • Relieve muscle pain and arthritis (See other herbs for inflammation)
  • Stimulate appetite

Used as a natural health remedy: Rosemary is used externally for the following benefits and conditions:

  • bath therapy (balneotherapy)
  • circulation problems
  • eczema
  • Hair loss, baldness – See formula below.*
  • insect repellent
  • joint and muscle pain (myalgia, sciatica, and intercostal neuralgia)
  • toothache
  • wound healing

*There is some evidence that a combination of essentil oils improves hair growth in 44% of people who try it. The formula of the herbal remedy for hair loss and bald spots (alopecia areata) is a combination of the following essential oils:

  • 3 drops (114 mg) of rosemary
  • 2 drops (88 mg) of thyme
  • 3 drops (108 mg) of lavender
  • 2 drops (94 mg) of cedarwood
  • 3 mL of jojoba oil
  • 20 mL of grapeseed oil

Each night, the mixture is massaged into the scalp for 2 minutes with a warm towel placed around the head to increase absorption. Although it’s not clear how rosemary works for hair loss, applying it to the scalp irritates the skin and increases blood circulation. Use for 6 months before assessing results.

Side Effects of Rosemary

There are no known side effects associtated with typical rosemary use.

As with any herb, a serious allergic reaction is possible. Seek immediate medical attention if you notice any symptoms of a serious allergic reaction. These may include a rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.

Overdose: Undiluted rosemary oil is UNSAFE to take by mouth. Taking large amounts of rosemary oil can cause vomiting, uterine bleeding, kidney irritation, photosensitivity, skin redness, and allergic reactions.

Other common names for rosemary include Compass Plant, Compass Weed, Encensier, Herbe Aux Couronnes, Old Man, Polar Plant, Romarin, Romarin Des Troubadours, Romero, Rose de Marie, Rose Des Marins, Rosée De Mer, Rosemarine, Rosmarinus officinalis, Rosmarinus, Rusmari, and Rusmary.

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