Softgels vs. tablets vs. capsules: what's the difference?

By Andres Zambrano Bravo

When developing new drug products, pharmaceutical companies often choose between three main dosage forms: tablets, hard capsules, and softgel capsules. This decision is a critical juncture in the development process, as each option has its own unique characteristics and benefits.

However, it's not just pharmaceutical companies that ponder this question. Consumers, too, often wonder about the differences between softgel capsules, tablets, and hard capsules. They may be curious about how these dosage forms affect the absorption, efficacy, and overall user experience of the medication.

For many people, the distinctions between these dosage forms may seem subtle or even negligible—but that’s far from the case. Indeed, understanding the unique characteristics of each can help people make more informed decisions when purchasing and using these products.

In this article, we'll explore the differences between softgel capsules, tablets, and capsules, and help you understand the pros and cons of each to make an informed decision. Based on our years of experience working with all three, we’ll also recommend a few suggestions so you can use the most effective product. 

What are softgel capsules?

Softgels, also known as soft gelatin capsules, are a type of liquid-filled capsule that consists of a gelatin-based shell encasing a liquid or semi-solid active ingredient. The fill is encapsulated in a hermetically sealed capsule shell.

Soft capsules come in a variety of sizes and shapes, with round, oval, and oblong being the most common. The size of these capsules is traditionally measured using the volumetric unit called a "minim". A minim is an old unit that represents the volume of a single drop, and it is equivalent to approximately 61.1 microliters (µl).

Advantages of softgel capsules

1. Improved Swallowability: The smooth, oval shape of softgel capsules facilitates easier swallowing compared to tablets or hard capsules, which can improve patient compliance.

2. Enhanced Bioavailability: The liquid or semi-solid content of softgel capsules can lead to better absorption and bioavailability of the active ingredient, as the dissolution process is often more rapid than with solid dosage forms. Some of the liquid ingredients used can improve bioavailability

3. Masking of Unpleasant Tastes and Odors: Softgel capsules can effectively conceal the taste and smell of the ingredients, making them more palatable for patients with sensitivities.

4. Liquid Ingredients: Softgel capsules are perfect for liquid ingredients, especially lipid, liquid content, such as fish oils, or vitamin D solutions, but also more complex formulations that enhance the bioavailability, are well compatible with softgel capsules.

Disadvantages of softgel capsules

1. Immediate Release: Softgel capsules are almost always immediate-release dosage forms, meaning they may not be suitable for medications or supplements that require a sustained or delayed release profile.

2. Gelatin: Softgel capsules are typically made using animal-derived gelatin, which may be a concern for individuals following a vegan or vegetarian lifestyle, or those with religious or cultural dietary restrictions. 

Softgels, for instance, may be preferred by individuals who have difficulty swallowing larger pills, as their smooth, rounded shape allows for easier ingestion. The liquid or semi-solid fill of softgel capsules can also lead to better absorption of the active ingredients, which may be particularly important for those with digestive issues or absorption difficulties.

What are tablets?

Tablets are solid, compressed forms of medication or supplements produced by compressing powdered ingredients into a small, hard, smooth-coated pill. 

Advantages of tablets

1. Cost-Effectiveness: Tablets are generally less expensive to manufacture compared to softgel capsules or hard capsules, making them a more affordable option for patients and healthcare systems.

2. Dosage Flexibility: Some tablets can be split or crushed, allowing for dosage adjustments when needed, which can be beneficial for patients requiring personalized dosing. Additionally, they offer a degree of versatility in terms of drug release profiles and dosage forms, and can be formulated to achieve characteristics such as delayed-release for targeted intestinal absorption, extended-release for prolonged drug delivery, or even colon-targeting for localized treatment.

Disadvantages of tablets

1. Swallowing Difficulties: Some patients, particularly those with dysphagia or a fear of choking, may find tablets harder to swallow due to their solid form and size, which can impact medication adherence.

2. Technological considerations: Tablets are also not always the best choice for every drug substance due to various technological or biopharmaceutical considerations, such as drug release profile and stability. 

Tablets are also easier to split or crush for those who need to adjust their dosage or have trouble swallowing whole pills. For companies, tablets can also be manufactured in different shapes, sizes, and colors, which can help with brand recognition and product differentiation.

What are hard capsules?

Hard capsules are a type of oral dosage form that consists of a hard or soft shell made from gelatin or other materials, encasing powdered or granulated ingredients. In contrast to soft capsules, the hard capsule shell contains only water, the polymer (gelatin or other), and potential colorants.

Advantages of hard capsules

1. Ease of Swallowing: Like softgel capsules, capsules have a smooth, rounded shape that makes them easier to swallow compared to tablets, which can improve patient compliance.

2. Customization Options: Capsules can be opened, and the contents can be mixed with food or beverages for patients who have difficulty swallowing pills, providing a degree of customization.

3. Versatility in Formulation: Capsules can accommodate a wide range of ingredients, including powders, granules, and liquids, making them suitable for a variety of active ingredients and formulations.

Disadvantages of hard capsules

1. Higher Costs: The production of capsules is more complex and costly compared to tablets, resulting in higher prices for consumers and healthcare systems.

2. Potential for Tampering: The ability to open capsules may raise concerns about potential tampering, which can be a consideration for certain medications or patient populations.

3. Technological constraints: not all formulations are compatible with the hard capsule shell.

Hard capsules, or two-piece hard capsules, offer a middle ground between softgel capsules and tablets. However, they can be opened and the contents mixed with food or drinks, providing a level of versatility for those with specific preferences or needs.

Which one is right for me?

The choice between softgel capsules, tablets, and hard capsules depends on a variety of factors, including the specific active ingredient, desired absorption profile, patient preferences, and cost considerations. 

Softgels offer enhanced absorption and palatability, as well as the possibility for single dosing of liquid formulations, including those that enhance the bioavailability of the drug. 

Tablets provide a cost-effective and stable option, and their release characteristics can be modified in many ways to achieve the target profile for the drug. However, they may present swallowing difficulties, and delayed or insufficient absorption. 

Hard capsules offer versatility and customization options but come with higher costs and potential tampering concerns. While they are suitable for the filling of lipid liquids, more complex liquid formulations cannot be encapsulated into hard capsules.

Pharmaceutical companies should consider these factors when selecting the most appropriate oral dosage form for their patients, weighing the advantages and disadvantages of each option to optimize medication efficacy, safety, and adherence.

Want more advice about which delivery form is right for you?

Our team offers the following:

+ Decades of experience in solid dosage form development
+ Support in the concept phase to establish the right dosage form for your product + Preparation of formulation concepts and target product profiles