Background

Calamus is a plant. The root (rhizome) is used to make medicine.

Despite safety concerns, calamus is commonly used for stomach problems, skin problems, earache, and to remove the smell of tobacco, but there is no good scientific evidence to support these uses.

In foods, calamus is used as a spice.

Safety Safety definitions

When taken by mouth: Calamus is LIKELY UNSAFE. The FDA prohibits calamus use in food products because three of the four species of calamus found in the world contain a cancer-causing chemical called beta-asarone. However, the amount of beta-asarone can vary widely among species from 0% to 96%, so some products may be safer than others. The most common side effect from calamus is vomiting. Fast heart rate and slowed intestinal movements have also been reported.

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 & Warnings:

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. In theory, large amounts of calamus might worsen heart problems in some people with heart conditions.

Low blood pressure: Calamus might lower blood pressure. In theory, taking calamus might make blood pressure become too low in people with low blood pressure.

Surgery: Calamus can affect the central nervous system. It might cause too much sleepiness if combined with medications used during and after surgery. If you are using calamus despite safety concerns, stop using it at least 2 weeks before a scheduled surgery.

Effectiveness

Dosing & administration

The appropriate dose of calamus depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for calamus. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Interactions with pharmaceuticals

Antacids

Interaction Rating=Minor Be watchful with this combination.

Antacids are used to decrease stomach acid. Calamus may increase stomach acid. By increasing stomach acid, calamus might decrease the effectiveness of antacids.

Some antacids include calcium carbonate (Tums, others), dihydroxyaluminum sodium carbonate (Rolaids, others), magaldrate (Riopan), magnesium sulfate (Bilagog), aluminum hydroxide (Amphojel), and others.

Drying medications (Anticholinergic drugs)

Interaction Rating=Moderate Be cautious with this combination.

Calamus might increase levels of certain chemical in the body that work in the brain, heart, and elsewhere. Some drying medications called "anticholinergic drugs" can also increase these chemicals, but in a different way. These drying medications might decrease the effects of calamus, and calamus might decrease the effects of drying medications.

Some of these drying medications include atropine, scopolamine, some medications used for allergies (antihistamines), and some medications used for depression (antidepressants).

Medications changed by the liver (Cytochrome P450 2D6 (CYP2D6) substrates)

Interaction Rating=Moderate Be cautious with this combination.

Some medications are changed and broken down by the liver. Although this has not been shown in humans, calamus might decrease how quickly the liver breaks down some medications. Taking calamus along with some medications that are broken down by the liver can increase the effects and side effects of these medications. Before taking calamus, talk to your healthcare provider if you are taking any medications that are changed by the liver.

Some medications changed by the liver include amitriptyline (Elavil), codeine, desipramine (Norpramin), flecainide (Tambocor), haloperidol (Haldol), imipramine (Tofranil), metoprolol (Lopressor, Toprol XL), ondansetron (Zofran), paroxetine (Paxil), risperidone (Risperdal), tramadol (Ultram), venlafaxine (Effexor), and others.

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)

Interaction Rating=Moderate Be cautious with this combination.

Some medications are changed and broken down by the liver. Although this has not been shown in humans, calamus might decrease how quickly the liver breaks down some medications. Taking calamus along with some medications that are broken down by the liver can increase the effects and side effects of these medications. Before taking clamus, talk to your healthcare provider if you are taking any medications that are changed by the liver.

Some medications changed by the liver include cyclosporine (Neoral, Sandimmune), lovastatin (Mevacor), clarithromycin (Biaxin), indinavir (Crixivan), sildenafil (Viagra), triazolam (Halcion), and many others.

Medications for depression (MAOIs)

Interaction Rating=Moderate Be cautious with this combination.

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

Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.

Medications for high blood pressure (Antihypertensive drugs)

Interaction Rating=Moderate Be cautious with this combination.

Calamus might reduce blood pressure. Taking calamus along with medications used for lowering high blood pressure might cause your blood pressure to go too low. Do not take too much calamus if you are taking medications for high blood pressure.

Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDiuril), furosemide (Lasix), and many others.

Medications that decrease stomach acid (H2-blockers)

Interaction Rating=Minor Be watchful with this combination.

Calamus might increase stomach acid. By increasing stomach acid, calamus might decrease the effectiveness of some medications that decrease stomach acid, called H2-blockers.

Some medications that decrease stomach acid include cimetidine (Tagamet), ranitidine (Zantac), nizatidine (Axid), and famotidine (Pepcid).

Medications that decrease stomach acid (Proton pump inhibitors)

Interaction Rating=Minor Be watchful with this combination.

Calamus might increase stomach acid. By increasing stomach acid, calamus might decrease the effectiveness of medications that are used to decrease stomach acid, called proton pump inhibitors.

Some medications that decrease stomach acid include omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium).

Sedative medications (CNS depressants)

Interaction Rating=Moderate Be cautious with this combination.

Calamus might cause sleepiness and drowsiness. Medications that cause sleepiness are called sedatives. Taking calamus along with sedative medications might cause too much sleepiness.

Some sedative medications include clonazepam (Klonopin), lorazepam (Ativan), phenobarbital (Donnatal), zolpidem (Ambien), and others.

Various medications used for glaucoma, Alzheimer disease, and other conditions (Cholinergic drugs)

Interaction Rating=Moderate Be cautious with this combination.

Calamus might increase certain chemicals in the brain, heart, and elsewhere in the body. Some medications used for glaucoma, Alzheimer disease, and other conditions also affect these chemicals. Taking calamus with these medications might increase the chance of side effects.

Some of these medications for glaucoma, Alzheimer disease, and other conditions include pilocarpine (Pilocar and others), donepezil (Aricept), tacrine (Cognex), and others.

Interactions with herbs & supplements

Herbs and supplements that might lower blood pressure: Calamus might reduce blood pressure. Using it along with other herbs and supplements that have the same effect might increase the risk of blood pressure dropping too low in some people. Some of these products include andrographis, casein peptides, cat's claw, coenzyme Q-10, fish oil, L-arginine, lycium, stinging nettle, theanine, and others.
Herbs and supplements with sedative properties: Calamus can affect the central nervous system and might cause sleepiness. There is a concern that using calamus with other herbs or supplements that also act like sedatives might cause too much sleepiness. Some of these products include 5-HTP, California poppy, catnip, hops, Jamaican dogwood, kava, St. John's wort, skullcap, valerian, yerba mansa, and others.

Interactions with foods

There are no known interactions with foods.

Action

It is thought that chemicals in calamus cause muscle relaxation and sleepiness. These chemicals might also reduce swelling, kill cancer cells, and kill insects.