This genus includes about 400 species of perennials, occurring mostly in temperate and mountainous areas of the northern hemisphere. Many are grown as ornamentals in a wide range of situations, including rock gardens and watersides. Primroses and cowslips are enduringly popular as garden plants, and naturalize well in grass. They should be planted well apart to avoid hybridization. Both species have a long history of use as medicinal herbs. Primula vulgaris was recommended by Pliny for paralysis, gout and rheumatism, and by Culpeper for healing wounds. Primula veris was once known as herba paralysis, radix arthritica, and "palsywort", due to its widespread use, dating back to at least medieval times, for conditions involving spasms, cramps, and paralysis, and rheumatic pain. Culpeper also prescribed the flowers, mixed with nutmeg, for "all infirmaties of the head", and referred to the use of the leaves "by our city dames" in cosmetics to enhance beauty and to treat "spots and wrinkles of the skin, sun-burning and freckles". Until cowslips became quite rare in this century, through habitat loss and modern farming practices, the flowers were collected each spring to make wine, which was taken largely as a sedative and nervine. Both species have similar constituents that may be used interchangeably; these include saponins, which have an expectorant effect, and salicylates (as in aspirin). Primula veris is now the more widely used.

In ancient times, the shape of the cowslip, a relative of the primrose , was thought to resemble a bunch of keys. The flower was dedicated to the Virgin Mary, thus its various common names: our lady's keys, key of heaven, and key flower. Used traditionally to treat respiratory conditions, cowslip has been shown in some studies to relieve symptoms of bronchitis just as well as standard medicines.

Small, clump-forming perennial with a short, stout rhizome, long, thing roots, and ovate-oblong leaves, 5-20cm (2-8in) long. Small, deep-yellow, fragrant, orange-marked flowers, with cylindrical pale green calyces, are borne in clusters in spring.

Common Name:
Other Names:
Butter Rose, Key Flower, Key of Heaven, Mayflower, Our Lady's Keys, Oxlip, Paigle
Botanical Name:
Primula veris
Dry, neutral to alkaline soil in sun or partial shade (P. veris). Moist, well-drained soil in sun or shade (P. vulgaris). Regular division is necessary to ensure vigor. Plants may be affected by rust, Botrytis, leafspot, and other fungal and viral diseases. Aphids, caterpillars, cutworms, and vine weevils may damage leaves.
By seed sown in late summer (species only); by division in late spring or early autumn.
Flowers (including calyx) are picked in spring and used fresh, or dried for use in infusions, ointments, and tinctures. Whole plant (P. vulgaris) is cut when flowering, and dried for use in infusions. Roots are lifted in spring (P. veris), or autumn of second year (P. vulgaris), and dried for decoctions and tinctures.
Native Location:
Europe and W Asia
15-20cm (6-8in)
15-20cm (6-8in)
Skin irritant and allergen.
Not given during pregnancy, or to patients sensitive to aspirin or taking anti-coagulant drugs (e.g. warfarin).
Parts Used:
Roots, Flowers
A sedative, expectorant herb that relaxes spasms and reduces inflammation.
Medicinal Uses:
Internally for bronchitis, mucus, dry cough, whooping cough, asthma, arthritis, insomnia, headache, and restlessness (especially in children). Externally for facial neuralgia, arthritic pain, skin blemishes, sunburn, and migraine.
Cowslip flower is used to treat insomnia, dizziness, headaches, bronchitis, and anxiety. Cowslip root is used to treat whooping cough, gout, bladder and kidney disease, rheumatoid arthritis, stomach cramps, and headaches. Germany's Commission E has approved the use of cowslip flower and cowslip root to treat cough and bronchitis.
Typical Dose:
A typical dose of cowslip flower is 1 to 2 ml of liquid extract, taken three times a day.
Possible Side Effects:
No side effects are known when cowslip is taken in recommended therapeutic dosages. However, allergic reactions are possible.
Drug Interactions:
Taking cowslip these drugs may increase the drug's effects:
Acetazolamide, (Apo-Acetazolamide, Diamox Sequels)
Alprazolam, (Apo-Alpraz, Xanax)
Amiloride, (Midamor)
Amobarbital, (Amytal)
Aspirin and Meprobamate, (Equagesic, 292 MEP)
Azosemide, (Diat)
Bumetanide, (Bumex, Burinex)
Buspirone, (BuSpar, Nu-Buspirone)
Butabarbital, (Butisol Sodium)
Carpipramine, (Defecton, Prazinil)
Chloral Hydrate, (Aquachloral Supprettes, Somnote)
Chlordiazepoxide, (Apo-Chlordiazepoxide, Librium)
Chlorothiazide, (Diuril)
Chlorthalidone, (Apo-Chlorthalidone, Thalitone)
Clorazepate, (Tranxene, T-Tab)
Dexmedetomidine, (Precedex)
Diazepam, (Apo-Diazepam, Valium)
Diphenhydramine, (Benadryl Allergy, Nytol)
Doxepin, (Sinequan, Zonalon)
Estazolam, (ProSom)
Ethacrynic Acid, (Edecrin)
Etozolin, (Elkapin)
Flurazepam, (Apo-Flurazepam, Dalmane)
Furosemide, (Apo-Furosemide, Lasix)
Glutethimide, (Glutethimide)
Haloperidol, (Haldol, Novo-Peridol)
Hydrochlorothiazide, (Apo-Hydro, Microzide)
Hydrochlorothiazide and Triamterene, (Dyazide, Maxzide)
Hydroflumethiazide, (Diucardin, Saluron)
Hydroxyzine, (Atarax, Vistaril)
Indapamide, (Lozol, Nu-Indapamide)
Lorazepam, (Ativan, Nu-Loraz)
Mannitol, (Osmitrol, Resectisol)
Mefruside, (Baycaron)
Mephobarbital, (Mebaral)
Meprobamate, (Miltown, Novo-Mepro)
Methazolamide, (Apo-Methazolamide, Neptazane)
Methyclothiazide, (Aquatensen, Enduron)
Metolazone, (Mykrox, Zaroxolyn)
Midazolam, (Apo-Midazolam, Versed)
Olmesartan and Hydrochlorothiazide, (Benicar HCT)
Oxazepam, (Novoxapam, Serax)
Pentazocine, (Talwin)
Pentobarbital, (Nembutal)
Phenobarbital, (Luminal Sodium, PMS-Phenobarbital)
Polythiazide, (Renese)
Promethazine, (Phenergan)
Propofol, (Diprivan)
Quazepam, (Doral)
Secobarbital, (Seconal)
Spironolactone, (Aldactane, Novo-Spiriton)
Temazepam, (Novo-Temazepam, Restoril)
Thiopental, (Pentothal)
Torsemide, (Demadex)
Triamterene, (Dyrenium)
Triazolam, (Apo-Triazo, Halcion)
Trichlormethiazide, (Metatensin, Naqua)
Trifluoperazine, (Novo-Trifluzine, Stelazine)
Urea, (Amino-Cerv, UltraMide)
Xipamide, (Diurexan, Lumitens)
Zaleplon, (Sonata, Stamoc)
Zolpidem, (Ambien)
Zopiclone, (Alti-Zopliclone, Gen-Zopiclone)
Culinary Uses:
Young leaves and flowers are added to salads; flowers are also candied and used for making country wines and tea.
Encyclopedia of Herbs by Deni Brown. Copyright © 1995, 2001 Dorling Kindersley Limited. pg 330
The Essential Herb-Drug-Vitamin Interaction Guide by Geo. T. Grossberg,MD and Barry Fox,PhD Copyright©2007 Barry Fox,PhD. Pp.173-174