Herbal Teas, Infusions and Decoctions Explained
What infusion, decoction, maceration and herbal tea mean, why the method changes what is in the cup, and what the sources say about safety. Definitions only, no recipes.
Content last updated . This page has not been medically reviewed.
Safety first. Natural products can cause side effects and interact with medicines. Read herb safety and interactions before you use anything on this page.
The question: is an infusion different from a decoction?
Yes. The two words describe different ways of getting a plant's compounds into water, and the difference can matter for both effect and safety. This page explains the terms as a medicines regulator defines them. It is a vocabulary guide, not a how-to. Individual teas are covered in Herbal Teas & Extracts, and the tea-making side is described on how herbal tea is prepared.
Some plants are poisonous or unsafe as teas. Never make a tea from a plant you cannot name from its label, and never from a plant you picked yourself without expert guidance. If someone may have swallowed a toxic plant, call Poison Help at 1-800-222-1222 (US), or 911 in an emergency. See poisoning: what to do first and Poison Help by country.
How the terms are defined
The EMA's Committee on Herbal Medicinal Products (HMPC) published a glossary in 2010 so that European herbal monographs use the same words. [1] In it:
| Term | EMA definition, in plain words |
|---|---|
| Herbal tea (tisane) | Plant material meant for a water-based drink made by infusion, decoction or maceration, prepared "immediately before use". |
| Infusion | Boiling water poured on the plant material and left to steep. EMA gives "usually 5 to 15 minutes" when nothing else is specified. |
| Decoction | Plant material starting in cold water, heated to the boil and simmered. EMA gives "usually" 15 to 30 minutes when nothing else is specified. |
| Maceration | Plant material soaked in water at room temperature. With gentle heating that stops short of boiling, EMA calls it "digestion". |
| Herbal tea mixture | A blend of several herbal substances. |
These are regulatory definitions of terms, not advice. The times shown are what the glossary uses when a monograph does not say otherwise.
Which method goes with which plant part
EMA says infusion is "usually" suited to leaves, flowers and delicate parts, while decoction or maceration suit roots, rhizomes and barks. It adds that decoction is "generally not applicable" to plant materials with volatile active constituents. [1] This is one reason knowing the plant part matters; see plant parts used in herbal products.
Why the method matters
EMA states the point directly: for herbal teas, instructions on the method may be crucial because "different preparations may exert different actions and in some circumstances may have a different safety profile". [1]
EMA also notes that boiling water is "important for lowering the microbial bioburden" of the plant material. [1] In plain terms, it can help reduce germs on dried plant matter.
A laboratory study shows the same idea from the safety side. Researchers tested 33 commercial teas and herbal teas bought in Spain and Portugal for two naturally occurring plant toxins (atropine and scopolamine). They found 64% of samples contaminated with one or both. They also found that brewing with boiling water for 5 and 10 minutes (the decoction method) allowed a higher extraction of these toxins into the water. [2] This is a finding about contamination in particular tea products, not about teas in general, and it does not tell you how to brew anything.
What research shows, and the limits
| Question | What the source found | Strength of evidence |
|---|---|---|
| Does the method change what ends up in the cup? | EMA says methods may produce different actions and safety profiles. A lab study found method changed toxin extraction in contaminated teas. [1] [2] | Regulator statement plus one laboratory study (not human outcomes) |
| Do human trials of teas compare methods? | Proper evidence not found. We read the EMA glossary and the monograph for valerian root and found no head-to-head human comparison. | Not applicable |
| Does a result for a tea apply to a capsule or tincture? | No. NCCIH notes, for green tea, that most cholesterol studies used extract supplements rather than the drink. [3] | Documented in NCCIH summary |
Traditional use versus research
Teas, decoctions and macerates are among the oldest ways people have used plants, in many regions. That history is traditional use: it describes what people did, not what trials proved. EU monographs treat "traditional use" as use "exclusively based upon long-standing use", and they list a herbal tea as one of the preparations for valerian root. [4]
Frequently asked questions
What is the difference between an herbal tea and an herbal infusion?
In the EMA glossary, an infusion is one method of making an herbal tea; "herbal tea" is also used for the finished drink. [1] In everyday use the words overlap.
Is a decoction stronger than an infusion?
The sources we read do not say. EMA defines them as different methods, and notes that different preparations may act differently. [1] "Proper evidence not found" for a general strength comparison.
Does boiling make a tea safe?
No. EMA says boiling water lowers microbes on the plant material. [1] It does not remove every risk: the laboratory study above found toxins in some teas, and brewing with boiling water extracted more of them. [2]
Why do teas on this site not have a recipe?
Some plants are unsafe as teas, and we cannot verify safe amounts for each person. A pharmacist or clinician decides what is right for you.
Can I swap a tea for a capsule?
Not safely on your own. Results and risks belong to the form tested. See herb forms and preparations.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety and who should ask first
- Medicines: herbs in tea can interact with medicines. See medication interactions. Ask a pharmacist.
- Children: the EU valerian monograph says use in children under 12 "has not been established due to lack of adequate data". [4] Ask a pediatric clinician before giving any herbal tea to a child. See children and teens.
- Pregnancy and breastfeeding: see pregnancy and breastfeeding.
- Quality: teas can be contaminated, as the study above shows. See herbal tea quality and labels.
- Dose: this site gives no amounts for readers. EU monographs list tea amounts as descriptions, not recommendations: EU monograph tea amounts.
References
- European Medicines Agency, Committee on Herbal Medicinal Products. Glossary on herbal teas, EMA/HMPC/5829/2010 Rev.1, 2010. Read 2026-10-23.
- Gonzalez-Gomez L, et al. Evaluation of Tropane Alkaloids in Teas and Herbal Infusions: Effect of Brewing Time and Temperature. Toxins 2023. PMID 37368663. Read 2026-10-23.
- NCCIH (US). Green Tea. Read 2026-10-23.
- European Medicines Agency, HMPC. European Union herbal monograph on Valeriana officinalis L., radix, EMA/HMPC/150848/2015, 2016. Read 2026-10-23.