The leaves and flowering heads of blessed thistle (Cnicus benedictus, Gaert.) are used medicinally by herbalists for various concerns. Not well studied, this plant has been used as a diaphoretic as well as an emmenagogue and for a variety of gastrointestinal complaints (for which it received an "Approved" status by the German Commission E).

Blessed thistle is unlikely to be used alone, and is probable only a minor contributing factor in multi-herb products for the above conditions. Blessed thistle should not be confused with milk thistle (Silybum marianum L.), a completely different plant.