Softgels, Hard Capsules and Tablets: Excipients and What the Shell Is Made Of
What softgels, hard capsules and tablets are made of beyond the active ingredient, how shells and fillers can matter for allergies and diets, and what tests found about breakdown.
Content last updated . This page has not been medically reviewed.
How the formats differ
| Format | What the sources say it is | Notes |
|---|---|---|
| Hard capsule | A shell that holds a powder or other solid fill. | Shells are made from gelatin or non-gelatin materials such as hypromellose and starch. [2] |
| Softgel (soft gelatin capsule) | A sealed shell around a liquid or semisolid fill. | A review lists delivering non-aqueous liquids and semisolids as an advantage of capsules over tablets. [2] Soft gelatin capsules are the most widely used pharmaceutical form after tablets. [3] |
| Tablet | A compressed unit of ingredient plus excipients. | The FDA says binders, excipients and fillers must be included in the ingredient statement. [4] |
Shell recipes include gelatin or a non-gelatin polymer, water, and with or without a plasticizer. [2] The shell can also be designed to change where the contents are released. [2] See enteric-coated and time-release supplements.
Allergies, intolerances and diets
- Food allergens. The FDA lists nine major food allergens: milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soybeans and sesame. [5] The page we read describes labeling for foods; we did not find on it how that rule applies to each supplement, so read the whole label and ask the maker or a pharmacist.
- Lactose. Lactose is one of the most commonly used excipients in pharmaceutical products, and a review concluded that most lactose-intolerant people tolerate the small amounts found in them; some people are sensitive. [6]
- Cellulose shells. A 2026 case report described a man with hives and swelling who tested positive to hypromellose (HPMC), a common capsule shell material. [7] One case cannot show how common this is.
- Animal-derived shells. The sources we read name gelatin and plant-based shells but do not describe where a given gelatin comes from. People avoiding animal products should read the label and ask the maker.
Does the shell change how well it breaks down?
Tests of dietary supplements show that dosage form is not a guarantee. In a study of 28 single-ingredient green tea supplements tested in several lots, 9 always passed a standard disintegration test, 8 always failed and 11 were inconsistent. [8] In a garlic study, powder capsules varied widely in allicin bioavailability (26% to 109% of a raw garlic reference). [9] Those are two ingredients, and results cannot be carried to every product. They show why quality testing matters: see quality testing and certifications.Swallowing difficulty
A Belgian pharmacy study found 5.9% of adults using oral solid medicines reported swallowing difficulties with at least one. [10] A review of medicines says improper crushing can reduce the dose a person receives and change how a drug acts. [11] We did not find the same question studied for supplements; ask a pharmacist before altering any product.Frequently asked questions
What is the difference between a softgel and a hard capsule?
A hard capsule holds a solid fill; a softgel is a sealed soft shell around a liquid or semisolid. [2] Neither is shown to work better in general; we found no broad head-to-head evidence.
Are capsule shells vegetarian?
Shells are made from gelatin or from non-gelatin materials such as hypromellose and starch. [2] Check the label; the sources we read do not say what any given product uses.
What are fillers and binders?
They are "other ingredients" used to make the unit; the FDA lists fillers, binders, excipients, preservatives, sweeteners and flavorings. [1]
Can a tablet fail to break down?
In one study of green tea supplements, some capsules and tablets failed a disintegration test. [8] That does not apply to every product.
Can I open a capsule or crush a tablet?
A review of medicines found improper crushing can reduce the dose received. [11] Proper evidence not found for supplements (we searched PubMed). Ask a pharmacist first.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
How to read the evidence labels
Labels used on this page: insufficient evidence, mixed, marketing claim. This is an information page about product types, not advice on what to take.
Safety and who should ask first
- Medicines: supplements may interact with medicines. [12] See medication interactions.
- Pregnancy, breastfeeding and children: many supplements have not been tested in these groups. [12]
- Surgery: some supplements may raise bleeding risk or affect anesthesia, so tell your care team well ahead. [12] See supplements before surgery.
- Kidney or liver disease: ask a clinician about every ingredient, including added ones. We did not find format-specific kidney or liver guidance in the sources read.
References
- FDA: Questions and Answers on Dietary Supplements. Read 2026-10-23.
- Gelatin and Non-Gelatin Capsule Dosage Forms (J Pharm Sci 2017). Read 2026-10-23.
- Shell Formulation in Soft Gelatin Capsules: Design and Characterization (Adv Healthc Mater 2024). Read 2026-10-23.
- FDA: Dietary Supplement Labeling Guide, Chapter IV, Nutrition Labeling. Read 2026-10-23.
- FDA: Food Allergies. Read 2026-10-23.
- Managing acute pain in patients who report lactose intolerance: the safety of an old excipient re-examined (2018). Read 2026-10-23.
- Hydroxypropyl methylcellulose-induced urticaria and angioedema: a case report (2026). Read 2026-10-23.
- Disintegration and Dissolution Testing of Green Tea Dietary Supplements (J Pharm Sci 2020). Read 2026-10-23.
- Allicin Bioavailability and Bioequivalence from Garlic Supplements and Garlic Foods (Nutrients 2018). Read 2026-10-23.
- Detection and management of pill swallowing difficulties: a community pharmacy-based observational study (2025). Read 2026-10-23.
- Crushed Tablet Administration for Patients with Dysphagia and Enteral Feeding (Drugs Aging 2023). Read 2026-10-23.
- NCCIH: Using Dietary Supplements Wisely. Read 2026-10-23.