Phleum Pratense

Last Editorial Review: 6/11/2021
Other Name(s):

Fléole des Champs, Fléole des Prés, Mil, Phléole des Champs, Phléole des Prés, Phleum pratense, Timothy, Timothy Grass.


Phleum pratense is a plant. The pollen from this plant is used as a medicine.

One kind of Phleum pratense preparation is put under the tongue to reduce symptoms of grass pollen allergies (hay fever).

A different kind of Phleum pratense preparation is injected under the skin to reduce symptoms of hay fever and other seasonal allergies.

How does it work?

Phleum pratense in very small doses is thought to desensitize the body to grass pollen allergies.


Asthma is a chronic respiratory disease. See Answer

Uses & Effectiveness

Possibly Effective for...

  • Grass pollen allergies (hay fever). Specific preparations of Phleum pratense seem to significantly reduce hay fever symptoms in people with asthma. The injectable form may also reduce asthma symptoms. Some evidence suggests that giving Phleum pratense over a span of 3 years to children with grass allergy prevents development of asthma.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Side Effects

Phleum pratense seems safe for most adults and children aged 3-16 years. When used under the tongue, Phleum pratense can cause itching and irritation of the mouth and nose, blisters in the mouth, and runny nose. When given by injection, it can cause irritation where the needle entered the skin.


What is Asthma? Asthma Myths Debunked See Slideshow

Special Precautions & Warnings

Pregnancy and breast-feeding: Not enough is known about the use of Phleum pratense during pregnancy and breast-feeding. Stay on the safe side and avoid use.


The following doses have been studied in scientific research:


  • For hay fever: 75,000 units of a specific standardized Phleum pratense allergen product (Grazax, Alk Abello) daily, starting 8 weeks before grass pollen season starts and continued until it ends.
  • For hay fever: 100,000 units of a specific Phleum pratense allergen product (Alutard SQ, Alk Abello) twice weekly starting 8 weeks before grass pollen season starts and continued until it ends.

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Ball T, Edstrom W, Mauch L, et al. Gain of structure and IgE epitopes by eukaryotic expression of the major Timothy grass pollen allergen, Phl p 1. FEBS J 2005;272:217-27. View abstract.

Brecker L, Wicklein D, Moll H, et al. Structural and immunological properties of arabinogalactan polysaccharides from pollen of timothy grass (Phleum pratense L.). Carbohydr Res 2005;340:657-63. View abstract.

Brimnes J, Kildsgaard J, Jacobi H, Lund K. Sublingual immunotherapy reduces allergic symptoms in a mouse model of rhinitis. Clin Exp Allergy 2007;37:488-97. View abstract.

Calderon M, Essendrop M. Specific immunotherapy with high dose SO standardized grass allergen tablets was safe and well tolerated. J Investig Allergol Clin Immunol 2006;16:338-44. View abstract.

Casanovas M, Sastre J, Fernández-Nieto M, et al. Double-blind study of tolerability and antibody production of unmodified and chemically modified allergen vaccines of Phleum pratense. Clin Exp Allergy 2005;35:1377-83. View abstract.

Dahl R, Stender A, Rak S. Specific immunotherapy with SQ standardized grass allergen tablets in asthmatics with rhinoconjunctivitis. Allergy 2006;61:185-90. View abstract.

Hannan JM, Marenah L, Ali L, et al. Insulin secretory actions of extracts of Asparagus racemosus root in perfused pancreas, isolated islets and clonal pancreatic beta-cells. J Endocrinol 2007;192:159-68. View abstract.

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Malling HJ, Lund L, Ipsen H, Poulsen L. Safety and immunological changes during sublingual immunotherapy with standardized quality grass allergen tablets. J Investig Allergol Clin Immunol 2006;16:162-8. View abstract.

Motta A, Peltre G, Dormans JA, et al. Phleum pratense pollen starch granules induce humoral and cell-mediated immune responses in a rat model of allergy. Clin Exp Allergy 2004;34:310-4. View abstract.

Motta AC, Dormans JA, Peltre G, et al. Intratracheal instillation of cytoplasmic granules from Phleum pratense pollen induces IgE- and cell-mediated responses in the Brown Norway rat. Int Arch Allergy Immunol 2004;135:24-9. View abstract.

Niggemann B, Jacobsen L, Dreborg S, et al. Five-year follow-up on the PAT study: specific immunotherapy and long-term prevention of asthma in children. Allergy 2006;61:855-9. View abstract.

Rak S, Yang WH, Pedersen MR, Durham SR. Once-daily sublingual allergen-specific immunotherapy improves quality of life in patients with grass pollen-induced allergic rhinoconjunctivitis: a double-blind, randomised study. Qual Life Res 2007;16:191-201. View abstract.

Roberts G, Hurley C, Turcanu V, Lack G. Grass pollen immunotherapy as an effective therapy for childhood seasonal allergic asthma. J Allergy Clin Immunol 2006;117:263-8. View abstract.

Rossi RE, Monasterolo G, Coco G, et al. Evaluation of serum IgG4 antibodies specific to grass pollen allergen components in the follow up of allergic patients undergoing subcutaneous and sublingual immunotherapy. Vaccine 2007;25:957-64. View abstract.