Overview

Calamus (Acorus calamus) is a grass-like plant found in swamps and near rivers. It has a long history of use in Ayurvedic and traditional Chinese medicine.

There are four different types of calamus. Some contain a cancer-causing chemical called beta-asarone. The North American and European varieties contain little to no beta-asarone, but others contain up to 96%. It also contains chemicals that might reduce pain and help fight infections.

People use calamus for asthma, cancer, depression, diabetes, headache, stomach ulcers, and many other conditions, but there is no good scientific evidence to support these uses. Using calamus can also be unsafe.

The US FDA banned calamus in 1968 due to some species containing the cancer-causing chemical beta-asarone.



Uses & Effectiveness

We currently have no information for Calamus overview.

Side Effects

When taken by mouth: Calamus is likely unsafe. The US FDA prohibits using calamus in food products because some species contain a cancer-causing chemical called beta-asarone. The amount of beta-asarone in calamus species can vary widely. In addition to cancer, side effects might include nausea and vomiting.

When applied to the skin: There isn't enough reliable information to know if calamus is safe or what the side effects might be.

Special Precautions and Warnings

When taken by mouth: Calamus is likely unsafe. The US FDA prohibits using calamus in food products because some species contain a cancer-causing chemical called beta-asarone. The amount of beta-asarone in calamus species can vary widely. In addition to cancer, side effects might include nausea and vomiting.

When applied to the skin: There isn't enough reliable information to know if calamus is safe or what the side effects might be.

Pregnancy and breast-feeding: Calamus is likely unsafe when taken by mouth during pregnancy or breast-feeding. Avoid use.

Heart conditions: Calamus might lower blood pressure and heart rate. Taking large amounts of calamus might worsen heart problems in some people with heart conditions.

Surgery: Calamus can affect the central nervous system. It might cause too much sleepiness if combined with medications used during and after surgery. Stop using calamus at least 2 weeks before a scheduled surgery.

Interactions

    Moderate Interaction

    Be cautious with this combination

  • Medications for depression (MAOIs) interacts with Calamus

    Calamus contains a chemical that affects the body. This chemical might increase the side effects of some medications used for depression.

    Some common MAOIs include phenelzine (Nardil), selegiline (Zelapar), and tranylcypromine (Parnate).

  • Medications changed by the liver (Cytochrome P450 2D6 (CYP2D6) substrates) interacts with Calamus

    Some medications are changed and broken down by the liver. Calamus might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

  • Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates) interacts with Calamus

    Some medications are changed and broken down by the liver. Calamus might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

  • Sedative medications (CNS depressants) interacts with Calamus

    Calamus might cause sleepiness and slowed breathing. Some medications, called sedatives, can also cause sleepiness and slowed breathing. Taking calamus with sedative medications might cause breathing problems and/or too much sleepiness.

  • Drying medications (Anticholinergic drugs) interacts with Calamus

    Calamus can increase a chemical in the body called acetylcholine. Acetylcholine plays a big part in many important body functions. Some medications, called anticholinergic drugs, block the effects of acetylcholine in the body. Taking calamus might decrease the effects of anticholinergic drugs.

  • Medications for high blood pressure (Antihypertensive drugs) interacts with Calamus

    Calamus might lower blood pressure. Taking calamus along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.

  • Various medications used for glaucoma, Alzheimer disease, and other conditions (Cholinergic drugs) interacts with Calamus

    Calamus can increase a chemical in the body called acetylcholine. Some medications that are used for glaucoma, Alzheimer disease, and other conditions, also increase acetylcholine levels. Taking calamus with these medications might increase the chance of side effects.

    Minor Interaction

    Be watchful with this combination

  • Antacids interacts with Calamus

    Antacids are used to decrease stomach acid. Calamus can increase stomach acid. Taking calamus might decrease the effects of antacids.

  • Medications that decrease stomach acid (H2-blockers) interacts with Calamus

    H2-blockers are used to decrease stomach acid. Calamus can increase stomach acid. Taking calamus might decrease the effects of H2-blockers.

    Some common H2-blockers include cimetidine (Tagamet), ranitidine (Zantac), and famotidine (Pepcid).

  • Medications that decrease stomach acid (Proton pump inhibitors) interacts with Calamus

    Proton pump inhibitors are used to decrease stomach acid. Calamus can increase stomach acid. Taking calamus might decrease the effects of proton pump inhibitors.

    Some common proton pump inhibitors include omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium).

Dosing

There isn't enough reliable information to know what an appropriate dose of calamus might be. It might also be unsafe. Speak with a healthcare provider before use.
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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

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