Do poppy seeds have negative side effects? A comprehensive guide

November 16, 2025 •

4 min read

Reports of product recalls due to dangerous opioid contamination have made headlines in recent years. But do poppy seeds have negative side effects when eaten in typical culinary amounts, or do these risks apply only to unwashed seeds and other uses? Understanding the difference is crucial for safe consumption.

Quick Summary

Food-grade poppy seeds are typically safe in small culinary amounts. However, using unwashed seeds for tea can cause lethal opioid toxicity. Other side effects include false-positive drug tests, rare allergic reactions, and bowel obstructions from eating very large quantities of raw seeds.

Key Points

Lethal Contamination: Unwashed poppy seeds used to brew tea can contain lethal doses of opioids like morphine and thebaine.
Safe for Food Use: Normal consumption of washed, food-grade poppy seeds is safe, with risks primarily associated with large quantities or improper use.
False-Positive Drug Tests: Consuming even standard food-grade poppy seeds can result in a positive urine test for opiates.
Rare Allergies: Though uncommon, allergic reactions to poppy seeds can occur, potentially causing anaphylaxis in sensitive individuals.
Bowel Obstruction Risk: Eating a very large, excessive amount of raw seeds may lead to a dangerous bowel blockage.
Processing Reduces Risk: Washing, soaking, and baking significantly reduce the trace levels of alkaloids present on poppy seeds.
Thebaine Toxicity: Specific contamination with the alkaloid thebaine has led to seizures, muscle spasms, and cardiac arrest.

The Primary Risk: Opioid Contamination

One of the most serious negative side effects associated with poppy seeds is opioid toxicity, but this danger is almost exclusively linked to unwashed seeds and home-brewed "poppy seed tea". The seeds themselves do not contain opiates, but they can become coated with the milky opium latex from the plant's pod during harvesting. Commercial, food-grade poppy seeds undergo a rigorous cleaning process to remove these compounds.

Unwashed seeds and tea: The greatest danger lies with unwashed seeds, often sold online and marketed for their high alkaloid content. Brewing these seeds into a tea can extract a lethal dose of morphine, codeine, and thebaine, leading to overdose symptoms like respiratory depression, cardiac arrest, seizures, and death. At least 19 deaths in the U.S. have been linked to poppy seed tea.
Food supply contamination: In rare cases, non-food grade seeds with high levels of toxic alkaloids like thebaine can inadvertently enter the food supply, leading to mass recalls. The risk from normally purchased food-grade seeds is minimal, but consumers should always be aware of food safety recalls.

Other Potential Side Effects and Concerns

Beyond opioid contamination, there are other potential issues associated with consuming poppy seeds, even the food-grade variety. These side effects are less severe but important to recognize.

False-Positive Drug Tests

One of the most well-known issues is the potential for a positive result on a drug screening for opiates. Even after thorough washing, trace amounts of alkaloids can remain on the seeds. Consuming a large number of baked goods with poppy seeds, such as multiple bagels or muffins, can lead to levels of morphine and codeine in the urine high enough to trigger an initial positive result. While confirmatory tests can often distinguish food consumption from drug use, it can still cause significant issues in employment, military, or sports settings.

Allergic Reactions

Though uncommon, poppy seed allergies do exist and can range from mild to severe. Symptoms can include hives, swelling, wheezing, and in rare cases, life-threatening anaphylaxis. Individuals with existing allergies to certain nuts and seeds like hazelnut, sesame, or kiwi may have a higher risk of a cross-reactive allergy to poppy seeds.

Bowel Obstruction

Ingesting excessively large quantities of raw poppy seeds can lead to a bowel obstruction, also known as bezoar formation. This is a rare occurrence but has been linked to fatalities in case reports. The combination of a large quantity of indigestible fiber from the seeds and insufficient hydration can cause a blockage in the digestive tract.

Safety Comparison: Washed vs. Unwashed Poppy Seeds

The difference in processing is key to understanding the safety of poppy seeds. Normal culinary seeds are treated to remove contaminants, while unwashed seeds are untreated.


Characteristic	Washed/Food-Grade Seeds	Unwashed/Non-Food Grade Seeds
Safety	Considered safe for consumption in normal culinary amounts.	Highly dangerous; not for human consumption.
Opioid Content	Negligible trace amounts. Alkaloid levels are significantly reduced during processing.	High and variable levels of morphine, codeine, and thebaine due to latex residue.
Culinary Use	Used as a spice, garnish, or ingredient in small quantities.	No culinary use. Often misused for home-brewed tea.
Risk of Toxicity	Extremely low risk when consumed normally.	High risk of severe opioid toxicity, overdose, and death.
Effect on Drug Test	Potential for false-positive results, depending on quantity consumed and testing sensitivity.	High probability of positive opiate test, confirming opioid exposure.

Conclusion: Navigating the Risks

While poppy seeds can offer nutritional benefits, it is clear that they do have significant negative side effects under specific, dangerous conditions. The primary risk stems from high-alkaloid contamination, particularly with unwashed seeds used for illicit tea brewing, which has proven fatal. In contrast, food-grade poppy seeds purchased from reputable sources are safe for typical culinary use.

For those who undergo drug testing, it is prudent to avoid poppy seed consumption entirely to prevent complications from a false-positive result. Rare but possible allergic reactions and the low risk of bowel obstruction from excessive raw intake are also factors to consider. Always purchase seeds from trusted retailers and consume them in moderation as part of a balanced diet. More information on plant toxins and food safety can be found on the Food Standards Agency website.

How to Safely Consume Poppy Seeds

To minimize risks, follow these steps when incorporating poppy seeds into your diet:

Purchase from trusted sources: Buy only food-grade poppy seeds from reputable retailers like major grocery stores, which have cleaned and processed the seeds to remove most alkaloids.
Avoid unwashed seeds: Do not purchase unwashed or specialty seeds from online sources or unknown vendors. Their opioid levels are unpredictable and highly dangerous.
Use in moderation: Stick to typical culinary quantities, such as those used for garnishing baked goods or in salad dressings.
Bake and cook: Heat treatment significantly reduces any remaining alkaloid levels on the seeds.
Check for recalls: Stay informed about potential food recalls, especially concerning spice and seed products.

Following these simple guidelines ensures that you can enjoy the flavor and nutritional value of poppy seeds while safely avoiding their negative side effects.

Frequently Asked Questions

No, you cannot get high from eating washed, food-grade poppy seeds. The trace amounts of opioids on commercially sold seeds are too low to cause any psychoactive effects. Getting high or experiencing toxicity only occurs from misusing unwashed seeds to make a dangerous tea.

Consuming poppy seeds can lead to a false-positive result for opiates on an initial drug screening. The trace alkaloids can be detected in urine for up to 48 hours. While later confirmatory tests can often distinguish food consumption from drug use, it can still cause complications in certain contexts.

Poppy seed allergies are rare, but they can be severe. Symptoms can range from hives and swelling to life-threatening anaphylaxis. The risk is higher for individuals with other nut or seed allergies.

Poppy seeds can become contaminated with opium latex containing alkaloids like morphine, codeine, and thebaine during harvesting. If seeds are sold unwashed, these high levels of toxic alkaloids remain, making them unsafe for consumption.

Poppy seed tea is a drink brewed from unwashed poppy seeds to extract their high concentration of opioids. It is extremely dangerous because the alkaloid levels are unpredictable and can easily cause a fatal overdose.

Small amounts of washed, food-grade poppy seeds are generally considered safe for children and pregnant women, similar to other culinary spices. However, larger medicinal amounts or unwashed seeds should be avoided.

Yes, washing, soaking, and heat treatment like baking can significantly reduce the level of opiate alkaloids on poppy seeds, further minimizing risk.