Herb library · Herb · Carthamus tinctorius
Safflower flower (hong hua)
The red-orange flower of the safflower plant, a dye and a Chinese herbal drug thought to act on the blood. The studies in people that were found are of injected extracts given in Chinese hospitals; nothing is known from studies about the flower taken by mouth. It was used historically to end pregnancies.
Traditional use
Brought to China from Central Asia in ancient times and grown widely for its flowers, which were used to dye cloth and to make rouge. In Chinese medicine the red flowers were thought to act on the blood: they were given to bring on menstruation, to cause abortion, and to expel a retained placenta. The seeds give an oil, today a common cooking oil; this page is about the flower, not the oil. In China today, purified flower extracts (safflower yellow) are made into injections for stroke, heart disease and blood clots.
What studies show
- Insufficient
The flower taken by mouth or as tea: the PubMed searches made for this entry found no studies of it in people, for any use.
- Insufficient
Stroke and blood clots (injected extracts, not the herb): many Chinese trials of safflower-yellow injections report better recovery after stroke and fewer clots after orthopedic surgery. A 2022 review of 120 stroke trials said its conclusions may be biased and that most trials did not track side effects; these hospital drugs say nothing about the flower as sold.
Be careful of
Cautions
- PregnancyDo not use it if you are pregnant or trying to become pregnant. Chinese medicine used the flower to bring on menstruation and to cause abortion (Stuart, 1911), and no safety studies in pregnancy were found.
- InteractionIts extracts are studied in China as add-ons to blood thinners, and they lengthened clotting times in those trials. If you take a blood thinner or have a bleeding disorder or upcoming surgery, talk with your clinician first.
- 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 flowers are extensively used for dyeing purposes and in the making of rouge. Medicinally, they are regarded as having stimulant, sedative, alterative, emmenagogue, and discutient properties.”
“They are also used to cause abortion and to expel a retained placenta.”
Sources
- Effect and Safety of Hydroxysafflor Yellow A for Injection in Patients with Acute Ischemic Stroke of Blood Stasis Syndrome: A Phase II, Multicenter, Randomized, Double-Blind, Multiple-Dose, Active-Controlled Clinical Trial (opens in a new tab) · NIH · read September 25, 2026
- Comparative efficacy of Honghua class injections for treating acute ischemic stroke: A Bayesian network meta-analysis of randomized controlled trials (opens in a new tab) · NIH · read September 25, 2026
- Safflower Yellow Combined with Low Molecular Weight Heparin in Preventing Deep Vein Thrombosis After Orthopaedic Surgery: A Meta-Analysis and Literature Review (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.