9 Dangerous Side Effects Of Cloves You Need To Know

Misuse of a popular spice could cause unexpected allergic and toxic reactions.

By Medha deb

Created on Sep 18, 2025

Misuse of a popular spice could cause unexpected allergic and toxic reactions.

Overview: Are Cloves Really Safe?

Cloves have long been treasured for their distinctive flavor and medicinal properties. Whether used as a spice in cooking, brewed into teas, or applied as clove oil for pain relief, cloves are a household staple. However, while cloves offer several health benefits, there is increasing recognition that excessive use or misuse can result in significant side effects. This article addresses the main dangerous side effects of cloves, as well as vital safety guidelines to keep in mind.

What Are Cloves?

Clove is the aromatic dried flower bud derived from the tree Syzygium aromaticum, native to Indonesia. Apart from culinary uses, cloves and clove oil (rich in the compound eugenol) are widely used in traditional remedies, dental care, and even as preservatives.

Top 9 Dangerous Side Effects of Cloves

1. Allergic Reactions

Some individuals develop moderate to severe allergic reactions to cloves or clove oil. Symptoms may manifest after ingestion or topical application and include:

Hives and skin rashes
Itching or swelling, particularly of the face, tongue, lips, or throat
Breathing difficulties
Redness and soreness (especially after dental use)
Mouth irritation, gum swelling, or ulcers when used orally

Allergic reactions may occur even with small amounts of clove oil and require immediate medical attention.

2. Toxicity from Clove Oil (Especially in Children)

While dietary use of whole cloves is generally safe, clove oil is highly concentrated and can be toxic if ingested in excessive amounts. Accidental consumption has resulted in:

Agitation, dizziness, and confusion
Severe liver injury (including hepatic necrosis)
Stupor, decreased consciousness, or even coma
Seizures
Hypoglycemia (very low blood sugar)
Respiratory depression

Children are exceptionally vulnerable, and serious poisoning can occur even with small amounts (10-30 ml, or 2-6 teaspoons). Cases often require hospitalization and may result in multi-organ complications, though most recover fully with prompt treatment.

3. Liver Damage

High doses of clove oil (primarily due to eugenol) can directly injure the liver. This may not occur with normal culinary use, but overdose—intentional or accidental—can lead to:

Nausea and upper abdominal pain
Loss of appetite, fatigue
Dark urine or clay-colored stools
Jaundice (yellowing of skin or eyes)
Signs of liver failure (elevated liver enzymes, coagulation abnormalities)

Liver damage from clove oil resembles the pattern seen in acetaminophen overdose, and infants are at highest risk.

4. Blood Sugar Fluctuations (Hypoglycemia)

One of the active compounds in cloves, eugenol, may both lower blood sugar and potentiate the effects of diabetes medications. This can result in hypoglycemia (dangerously low blood glucose), especially for individuals:

With diabetes
On insulin or other blood sugar-lowering drugs

Symptoms can include dizziness, sweating, confusion, rapid heartbeat, and in severe cases, fainting or seizures. It is vital for individuals with diabetes to discuss clove supplements with their healthcare provider before use.

5. Drug Interactions

Cloves—especially clove oil and supplements—may interact with various pharmaceutical medications:

Increased risk of bleeding when combined with blood thinners like warfarin (due to the anti-platelet action of eugenol)
Amplified effects of hypoglycemic drugs, leading to low blood sugar

Anyone on anticoagulant or anti-platelet medications, or those with underlying bleeding disorders, should seek medical advice before using significant amounts of cloves.

6. Respiratory Distress

Inhaling clove oil vapor or aerosols may irritate respiratory passages and can be particularly harmful for asthma sufferers or individuals with chronic respiratory diseases. Symptoms include:

Shortness of breath or coughing
Chest tightness
Wheezing

In severe cases, breathing difficulties may require emergency medical attention.

7. Mouth and Gum Irritation

Oral use of clove oil or products containing eugenol is a time-honored dental remedy for toothache and sore gums. However, applying undiluted clove oil or using it frequently can cause:

Mouth sores
Sore, swollen, or bleeding gums
Altered tooth color or sensitivity

Repeated topical application may also result in allergic contact reactions or oral tissue burns.

8. Delayed Ejaculation and Reproductive Effects

Some men report trouble achieving orgasm or experiencing delayed ejaculation when using clove oil-containing products for enhancing sexual performance or as topical anesthetics. Limited scientific data confirm this effect, but anecdotal evidence and case reports exist.

9. Hazardous Use in Pregnancy and Infancy

There is insufficient safety data on the use of cloves, clove oil, or related products during pregnancy and breastfeeding. Key concerns include:

Potential stimulation of uterine contractions (when used in large or medicinal quantities)
Risk of liver damage in infants exposed to clove oil, even via topical routes

Pregnant and breastfeeding women should avert medicinal doses of cloves and always consult their healthcare provider before use.

Other Reported Clove Side Effects

Skin irritation: Clove oil can cause mild to moderate rashes, itching or burning when applied undiluted.
Gastrointestinal upset: High doses or frequent use may cause nausea, vomiting, diarrhea, and abdominal pain in sensitive individuals.
Infections: Rarely, improper use may contribute to infections of the mouth or gums if hygiene is compromised.

Clove Oil: More Dangerous Than Whole Cloves?

Clove oil is about 80–90% eugenol, while whole or ground cloves contain much smaller amounts. Therefore, toxicity and side effects are far more likely to occur with the oil, especially if it is swallowed undiluted or used in large amounts. Always use clove oil under medical supervision, and keep it well out of the reach of children.

Who Should Avoid Cloves?

Risk Group	Potential Hazards
Infants and Young Children	Liver injury, seizures, severe toxicity
Pregnant/Breastfeeding Women	Poorly studied safety; possible uterine stimulation or infant toxicity
Those on Blood Thinners (e.g. warfarin)	Increased bleeding risk due to interaction
People with Bleeding Disorders	Potential worsening of bleeding
Diabetics (on medication)	Hypoglycemia from blood sugar lowering effects
Individuals with Allergies to Eugenol	Severe allergic reactions

How to Use Cloves Safely

Use whole or ground cloves as a culinary spice in moderate amounts.
Avoid using undiluted clove oil on skin or gums; always dilute as per guidelines.
Never give clove oil, even in tiny amounts, to young children.
Consult a physician before using clove supplements or oils, especially if pregnant, breastfeeding, diabetic, or taking medications.
Discontinue use immediately and seek medical help if you experience allergic reactions, severe digestive pain, jaundice, or any signs of toxicity.

Frequently Asked Questions (FAQs)

Q1. Is it safe to chew clove daily?

For most healthy adults, chewing one or two cloves as a freshener is considered safe. However, excessive daily consumption may increase the risk of side effects, especially in those with underlying health conditions or individuals taking certain medications.

Q2. Can cloves be harmful for children?

Yes. Small children are particularly at risk for toxicity if they ingest clove oil or large quantities of cloves. Adverse effects can include liver injury, central nervous system symptoms, and even life-threatening complications; cloves and clove oil should be kept out of reach of children at all times.

Q3. What are the signs of clove or clove oil allergy?

Typical allergic reactions include redness, soreness, swelling, rash, hives, mouth irritation, and in severe cases, breathing difficulty and anaphylaxis. Discontinue use and seek medical attention if such symptoms appear.

Q4. Does clove interact with medications?

Yes. Cloves (especially the oil or concentrated supplements) interact with blood thinners and diabetes medications, potentially increasing the risk of bleeding or hypoglycemia. Always inform your doctor about clove use if you are taking prescription drugs.

Q5. Can pregnant women use cloves safely?

Regular culinary use of cloves is generally considered safe, but medicinal or supplemental doses are discouraged during pregnancy and breastfeeding due to insufficient safety data and potential risks.

Conclusion

While cloves are a flavorful spice with beneficial properties, they must be used conscientiously. Clove oil toxicity, allergic reactions, drug interactions, and dangerous effects in vulnerable groups make it essential to moderate clove consumption, comply with usage guidelines, and consult healthcare professionals when needed. Always prioritize safety, especially when using potent natural remedies.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

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