What is it used for?
All oral dosage forms
Helps (temporarily) to support/promote alertness and wakefulness, and to enhance cognitive performance [Source note 4].
Helps (temporarily) to support/promote mental sharpness/alertness [Source note 5].
Helps (temporarily) to relieve/reduce fatigue, to promote endurance, and to enhance motor performance [Source note 6].
Helps (temporarily) to enhance (physical) energy [Source note 7].
Helps (temporarily) to relieve/reduce fatigue/tiredness [Source note 8].
Oral dosage forms except energy shots (liquid (shot))
Used (temporarily) as a mild diuretic [Source note 9].
Notes:
The above uses can be combined on the product label (e.g. Helps temporarily to support mental alertness and reduce fatigue).
The terms ‘Helps’ or ‘Helps to’ can be used interchangeably on the label.
What this guide covers
this reference only supports caffeine as a pure chemical substance and does not support any extract preparations.
Uses or Purposes Restrictions when this reference is combined with other references (source review category II and III):
Products containing caffeine from any source (synthetic, isolated or a component of plant material) must not:
indicate any uses or purposes related to healthy blood pressure or cardiovascular health at any dose of caffeine except if supported by a reference for a specific caffeine-containing active ingredient such as green coffee bean extract.
indicate any uses or purposes related to nervine/sedative/relaxation, nor contain a sedative at therapeutic dose, at any dose of caffeine.
indicate any uses or purposes related to the maintenance/support of good/general health at a daily dose of 40 mg or more total caffeine from all sources.
Products providing a total amount of caffeine per day that meets the minimum therapeutic dose (100 mg/day) must indicate a use or purpose associated with caffeine.
source review category II and III for products providing more than 400 mg of total caffeine per day cannot make any claims other than the ones listed on this reference, or those from references with compatible recommended conditions of use (e.g., Workout Supplements reference appendices of acceptable claims for products recommended for occasional use only). source review category III may include additional claims if evidence is provided to support the safety and efficacy of the product according to the recommended conditions of use required for products providing more than 400 mg of total caffeine per day.
Who does this guide cover?
Adults 18 years and older
How is it taken?
Oral [Source note 2]
Which forms are covered?
this reference does not apply to caffeine added to food. Caffeine is regulated as a food additive when it is added to foods, including beverages, chewing gum, and bars. Questions about using caffeine in food can be sent to the Food Directorate (food-aliment@hc-sc.gc.ca).
For caffeinated energy shots, select "liquid (shot)".
Note: A caffeinated energy shot is defined as a pre-packaged, ready-to-consume product with a volume of 90 mL or less and meant to be consumed at once [Source note 3].
Quantities
Mild diuretic
100 - 200 milligrams of caffeine, per single dose; Not to exceed 800 milligrams, per day [Source note 10].
Other uses
100 - 200 milligrams of caffeine, per single dose; Not to exceed 1000 milligrams, per day [Source note 11].
Energy shots (liquid (shot))
100 - 200 milligrams caffeine, per single dose (= per shot); Not to exceed 400 milligrams, per day [Source note 12].
How is it used?
Products providing more than 200 mg caffeine, per day (i.e. to be taken in divided doses or, for shots, if the recommended daily dose includes more than one single dose (= shot) providing more than 100 mg caffeine each)
Wait 3 to 4 hours between each dose.
Energy shots (liquid (shot))
Do not mix with alcohol [Source note 13].
How long is it used?
Mild diuretic or products providing more than 400 mg of caffeine, per day
For occasional use only [Source note 14]
Warnings and precautions
Products providing 100 mg to 400 mg caffeine, per day¹
Ask a healthcare professional before use if you have high blood pressure or glaucoma (Cornelis and El-Sohemy 2007, Chandrasekaran et al. 2005, Noordzij et al. 2005, Avisar et al. 2002, Arya et al. 2000, Jee et al. 1999, Creighton and Stanton 1990).
¹Note: This statement is also required at subtherapeutic quantities for products providing 40 mg or more caffeine per day from all sources for source review category II and III.
Products providing more than 300 mg caffeine, per day
Ask a healthcare professional before use if you are pregnant, breastfeeding, or attempting to conceive [Source note 15].
Products providing 400 mg or more caffeine, per day
When using this product avoid taking other health products, foods or beverages that contain caffeine and/or increase blood pressure [Source note 16].
When should it be avoided?
Products providing more than 400 mg caffeine per day
Do not use if you have high blood pressure or glaucoma (Cornelis and El-Sohemy 2007, Chandrasekaran et al. 2005, Noordzij et al. 2005, Avisar et al. 2002, Arya et al. 2000, Jee et al. 1999, Creighton and Stanton 1990).
Possible side effects
All products
Stop use and ask a healthcare professional if hypersensitivity/allergy occurs [Source note 17].
Products providing 200 mg or more caffeine, per day
Stop use and ask a healthcare professional if symptoms such as chest pain and irregular heartbeat occur [Source note 18].
Products providing more than 400 mg caffeine, per day
Stop use and ask a healthcare professional if nervousness, anxiety, insomnia, tremor and/or headache occur (IOM 2001, Zhang 2001, Sawynok 1995).
All products except those making a diuretic claim¹
When using this product diuretic effect may occur.
¹Note: This statement is also required at subtherapeutic quantities for products providing 40 mg or more caffeine per day from all sources for source review category II and III.
Storage
Must be established in accordance with the requirements described in the applicable product regulations.
Preparation details
Ingredient identity, preparation requirements, and other details that define the scope of this guide.
Ingredients and preparations
| Proper name(s) | Common name(s) | Source information / Source ingredient(s) | Source information / Source material(s)¹ | Source information / Part(s) |
|---|---|---|---|---|
| Caffeine |
| N/A | N/A |
| Caffeine | N/A | Camellia sinensis | Leaf |
| Caffeine | N/A |
| Seed |
| Caffeine | N/A | Cola acuminata | Seed |
| Caffeine | N/A |
| Leaf |
| Caffeine | N/A | Paullinia cupana | Seed |
| Caffeine | N/A | Theobroma cacao | Seed |
References: Proper names: USP-NF 2023; Common name: USP-NF 2023; IOM 2003; Source information: Ashihara and Suzuki 2004; Zajac et al. 2003; Duke 2001; Gennaro 2000.
¹Source materials listed in Table 1 are only allowed if caffeine is isolated and purified from these source materials and has a molecular structure which is identical to that which it had prior to its isolation. this reference only supports caffeine as a pure chemical substance and does not support any extract preparations. ²Synthetic.
Other ingredients
Must be chosen from the current source ingredient database and must meet the limitations outlined in the database.
Preparation and quality requirements
The finished product specifications must be established in accordance with the requirements described in the source authority source’s product quality guidance.
The active ingredient must comply with the requirements outlined in the source ingredient database.
Guide change history
Updates to this SupplementSafety.org guide.
Minor updates
Updated guide wording, organization, and source presentation. Added our editorial change history.
Initial release
Initial SupplementSafety.org guide prepared from source reference material.
Validation: Not yet completed. Editorial updates do not constitute clinical validation.
Sources
Source information
This guide organizes source material about uses, preparations, amounts, and precautions. Read the conditions alongside each statement; the information may apply only to particular preparations or populations.
The source document includes supporting references. We have not independently summarized or assessed every cited study for this guide.
- Source document version
- December 19, 2025
- Source captured
- Aug 15, 2026
- Editorial work
- Editorial preparation. Independent clinical review has not been recorded for this guide.
Full citations are available through the link above. Verification is required to open them; reading this guide does not require verification.
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