Overview

Quassia is a plant. The wood and sometimes the leaf are used as medicine.

People use quassia for stomach and intestinal problems, diabetes, lice, skin conditions, and many other conditions, but there is no good scientific evidence to support most uses.

In manufacturing, quassia is used to flavor foods, beverages, lozenges, and laxatives. The bark and wood have been used as an insecticide.

How does it work ?

Quassia contains chemicals that might prevent the parasite that causes malaria from growing and kill the mosquito larvae. These chemicals might also increase stomach acid and bile secretions, perhaps accounting for appetite stimulant and digestive effects.

Uses & Effectiveness ?

Insufficient Evidence for

  • Lice. Early research suggests that a single application of quassia tincture can kill head lice. But the lice might come back. Some research shows that two applications within one week might be more effective than a single application.
  • A skin condition that causes redness on the face (rosacea). Applying a gel containing quassia to the skin might reduce redness and flushing in people with rosacea. But higher quality research is needed to confirm.
  • Rough, scaly skin on the scalp and face (seborrheic dermatitis). Applying a gel containing quassia to the skin might help clear up seborrheic dermatitis in some people. But higher quality research is needed to confirm.
  • Diabetes.
  • Appetite loss.
  • Indigestion.
  • Constipation.
  • Fever.
  • Intestinal worms.
  • Other conditions.
More evidence is needed to rate the effectiveness of quassia for these uses.

Side Effects

When taken by mouth: Quassia is LIKELY SAFE when taken by mouth in food amounts. But quassia is POSSIBLY UNSAFE when taken by mouth as medicine. It can cause side effects such as irritation of the mouth, throat, and digestive tract along with nausea and vomiting. In very large doses, it could cause abnormal heart function. But most people throw up before they get a high enough dose to cause heart problems. Long-term use can cause vision changes and blindness.

When applied to the skin: Quassia is POSSIBLY SAFE when applied to the skin.

When given as an enema (rectally): There isn't enough reliable information to know if quassia is safe or what the side effects might be.

Special Precautions and Warnings

When taken by mouth: Quassia is LIKELY SAFE when taken by mouth in food amounts. But quassia is POSSIBLY UNSAFE when taken by mouth as medicine. It can cause side effects such as irritation of the mouth, throat, and digestive tract along with nausea and vomiting. In very large doses, it could cause abnormal heart function. But most people throw up before they get a high enough dose to cause heart problems. Long-term use can cause vision changes and blindness.

When applied to the skin: Quassia is POSSIBLY SAFE when applied to the skin.

When given as an enema (rectally): There isn't enough reliable information to know if quassia is safe or what the side effects might be.

Pregnancy and breast-feeding: Quassia is LIKELY UNSAFE when taken by mouth during pregnancy or breast-feeding. It can cause cell damage and nausea. Avoid using.

Diabetes: There is a concern that quassia might lower blood sugar levels. If you have diabetes and use quassia, be sure to monitor your blood sugar levels carefully. Check with your healthcare provider to see if the dose of diabetes medications you are taking needs to be lowered.

Digestive tract problems or diseases, such as stomach or intestinal ulcers, Crohn's disease, infections, and many other conditions: In large amounts quassia can irritate the digestive tract. Don't use it if you have one of these conditions.

Surgery: Quassia might lower blood sugar levels. There is some concern that it might interfere with blood sugar control during and after surgery. Stop using quassia at least 2 weeks before a scheduled surgery.

Interactions ?

    Moderate Interaction

    Be cautious with this combination

  • Digoxin (Lanoxin) interacts with QUASSIA

    Quassia is a type of laxative called a stimulant laxative. Stimulant laxatives can decrease potassium levels in the body. Low potassium levels can increase the risk of side effects of digoxin (Lanoxin).

  • Water pills (Diuretic drugs) interacts with QUASSIA

    Quassia is a laxative. Some laxatives can decrease potassium in the body. "Water pills" can also decrease potassium in the body. Taking quassia along with "water pills" might decrease potassium in the body too much.

    Some "water pills" that can decrease potassium include chlorothiazide (Diuril), chlorthalidone (Thalitone), furosemide (Lasix), hydrochlorothiazide (HCTZ, HydroDiuril, Microzide), and others.

  • Medications changed by the liver (Cytochrome P450 1A1 (CYP1A1) substrates) interacts with QUASSIA

    Some medications are changed and broken down by the liver. Quassia might decrease how quickly the liver breaks down some medications. Taking quassia along with some medications that are changed by the liver might decrease how quickly these medications are broken down by the liver. Before taking quassia talk to your healthcare provider if you take any medications that are changed by the liver.

    Some medications that are changed by the liver include chlorzoxazone, theophylline, bufuralol, and others.

  • Medications for diabetes (Antidiabetes drugs) interacts with QUASSIA

    Quassia might decrease blood sugar levels. Diabetes medications are also used to lower blood sugar. Taking quassia along with diabetes medications might cause your blood sugar to drop too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

    Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

    Minor Interaction

    Be watchful with this combination

  • Antacids interacts with QUASSIA

    Antacids are used to decrease stomach acid. Quassia may increase stomach acid. By increasing stomach acid, quassia 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.

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

    Quassia might increase stomach acid. By increasing stomach acid, quassia 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) interacts with QUASSIA

    Quassia might increase stomach acid. By increasing stomach acid, quassia 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).

Dosing

The appropriate dose of quassia 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 quassia. 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.
View References

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.

This copyrighted material is provided by Natural Medicines Comprehensive Database Consumer Version. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version.
© Therapeutic Research Faculty 2020.