Aromatherapy Science Online


This interactive course immerses students in the fundamental principles of aromatherapy. This course experience begins with the historical beginnings of aromatherapy in ancient cultures and follows the development of this unique integrative modality through modern evidence-based clinical aromatherapy. Students explore the science of the sense of smell and the psychological and physiological effects of aroma. Essential oil materia medica is introduced via hands-on practical labs where students prepare aromatherapy formulas correlating to the essential oils studied. Students also explore methods of essential oil extraction and the types of chemical constituents found in essential oils. Research related to clinical aromatherapy for specific populations, key safety considerations, and regulatory guidelines are also explored. This class is a fantastic resource for anyone working in integrative health.

Learning Outcomes

  • Compare modern aromatherapy definitions, philosophy, practices, and essential oil distillation with their historic development.

  • Summarize key information from peer-reviewed, published aromatherapy research focused on essential oil therapeutic actions, mechanisms, clinical applications, or industrial uses.

  • Describe the organoleptic assessment, therapeutic uses, methods of extraction, key constituents, and example formulations of selected essential oils.

  • Explain how essential oils create therapeutic effects via physiological and psychological mechanisms, including olfaction and psychoneuroimmunology.

  • Evaluate the potential role of aromatherapy for special populations including gynecology and obstetrics.

  • Discuss key essential oil and aromatherapy safety concerns and best practices, including differences in regulatory requirements internationally.

  • Identify industrial uses of essential oils, including commercial flavor and fragrance.

More details

Required Materials (Course Pack)

  • ACHS eTextbook: Petersen, D. (2020). Aromatherapy Materia Medica: Essential Oil Monographs (20th Edition). Portland, OR: American College of Healthcare Sciences. (Optional: Printed copy available for an additional fee)
  • Online Materials and Library Resources (OMLR)
  • AROMA 501 Practical Lab Kit

The AROMA 501 Practical Lab Kit includes the following certified organic or sustainably wildcrafted essential oils:   

  • Bergamot Citrus aurantium var. bergamia
  • Chamomile Roman Chamaemelum nobile 
  • Clary Sage Salvia sclarea
  • Cypress Cupressus sempervirens var. stricta
  • Eucalyptus Globulus Eucalyptus globulus
  • Eucalyptus smithii Eucalyptus smithii
  • Geranium Pelargonium graveolens
  • Ginger Zingiber officinale
  • Juniper Berry Juniperus communis
  • Lavandin Lavandula intermedia
  • Lavender Lavandula angustifolia
  • Lemon Citrus limonum
  • Lemon Eucalyptus Eucalyptus citriodora
  • Lime Citrus aurantiifolia
  • Neroli Citrus aurantium var. amara
  • Peppermint Mentha xpiperita var. Black Mitcham
  • Pine Pinus sylvestris
  • Rose Attar Rosa damascena
  • Rosemary Rosmarinus officinalis
  • Sandalwood Santalum album
  • Sweet Orange Citrus sinensis
  • Tea Tree Australia Melaleuca alternifolia
  • Tea Tree New Zealand Leptospermum scoparium
  • Ylang Ylang Cananga odorata

This practical lab kit also contains the following experiential learning supplies:

  • 1 oz Amber bottles with dropper (Qty 4)
  • 10 ml Roll-on bottles (Qty 3)
  • 2 oz Cobalt blue spray bottle
  • 2 oz Camellia Oil
  • 16 oz Sweet Almond Oil (may contain multiple bottles to total 16oz)
  • 25 ml glass beaker & glass stirring rod
  • 3 ml disposable pipettes (Qty 6)
  • Perfume Testing Strips
  • 5 ml amber bottle (Qty 4)
  • Nasal inhalers (Qty 3)
  • Laminated Essential Oil Chart

Required Textbooks: 

View the required textbooks for this class, including ISBN, edition, and retail price, by visiting our Required Textbooks page.

Total Course Price:

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Current Instructors:

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Admissions Requirements:

Candidates must possess a baccalaureate degree or higher from an institution accredited by an agency recognized by the US Department of Education. Candidates must submit official transcripts directly from the issuing institution along with one professional letter of recommendation. All applicants must be recommended for admission by the ACHS Admissions Committee.

Total Course Price:

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