Herb library · Herb · Stachytarpheta jamaicensis
Vervain (Jamaican vervain)
A roadside weed with long spikes of small blue-violet flowers, brewed in Trinidad and Jamaica as a "cooling" bush tea. It has lab and animal studies only; no trial in people has been done.
Traditional use
In Trinidad vervine is one of the most-cited plants for a "cooling" or "cleanser" tea, and older people across its range take it as a cooling tonic. It has also been used for dysentery and worms, fever, colds and to increase breast milk. Not the same plant as European vervain.
Traditional energetics
Caribbean folk tradition
Counted as cooling. An ethnobotanical survey of medicinal plants in Trinidad (J Ethnobiol Ethnomed, 2015) — full text on PubMed Central · NIH (opens in a new tab)
What studies show
No studies in people of this herb on its own yet. What is known of it comes from the traditions that use it.
- Insufficient
Pain, inflammation, stomach ulcers, blood sugar and infections: a 2016 review describes antimicrobial, anti-inflammatory and other effects in lab and animal studies. No clinical study in people was found.
Be careful of
Cautions
- PregnancyThe 2016 review says it is not recommended for pregnant women, because it is considered to be able to cause miscarriage.
- ConditionThe same review advises against it for people with low blood pressure, because it is considered to lower blood pressure.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“The expressed juice of the plant, dose one or two table spoonfuls, a cooling purge for children in fevers and worms.”
“This plant is poisonous to sheep. Its virtues as a purifier of the blood are well known, even when used as tea.”
Sources
- Stachytarpheta jamaicensis (L.) Vahl: from traditional usage to pharmacological evidence (Evid Based Complement Alternat Med, 2016) — full text on PubMed Central (opens in a new tab) · NIH · read September 25, 2026
- An ethnobotanical survey of medicinal plants in Trinidad (J Ethnobiol Ethnomed, 2015) — full text on PubMed Central (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.