Difference Between Drug & Dosage Form

In this article, we are going to discuss one of the most common & confusing questions asked regarding the difference between drug and dosage form.

The explanation will be very simple & precise to clear your concept. First of all, we will discuss what is a drug.


As we are here to build your basic concepts so we will not go into complex definitions of drug, We will define drug as,

Drug & Dosage Form Difference


Definition Of Drug 

A drug is an active pharmaceutical Ingredient which gives biological or pharmacological effects.

Any substance which gives a therapeutic effect is known as a drug.


To treat fever the substance Paracetamol is prescribed so the substance Paracetamol is a drug or API because it provides therapeutic effects to relieve the fever.

Now we will describe what is dosage form but before going into details of dosage form first of all we will explain what is a dose.

What Is Dose?

The calculated amount of a drug which is prescribed by the practitioner to the patient to take at specified time intervals for achieving desired therapeutic effects is known as a Dose.


Continuing the above example of Paracetamol, if a practitioner prescribed that take 500 mg of Paracetamol three times a day then it is the dose of paracetamol.

Dosage Form 

As we discussed earlier the drug is an API means purely API is known as drug.So what is dosage form?

The combination of drug and an inert material is known as Dosage Form. The inert materials are known as excipients so the combination of active pharmaceutical ingredients & excipients is known as the dosage form.

API + Excipients = Dosage Form 

Explanation Of Dosage Form 

Read the dosage form with some modifications like reverse reading as given below,

Dosage Form 

After modification & reading reverse

“Form Of Dosage or Form Of Dose”

Now check the definition of Dosage Form,

The form of a dose is known as the dosage form.


The form of a drug is known as the dosage form.


The physical form of a drug in which it is available in the market to use by a specific route for therapeutic purposes is known as Dosage Form.


The finalized form of a finished product is dosage form.


Paracetamol is purely a drug (API) but we know that we can not take API alone for therapeutic purposes; it always requires some excipients for its transportation, stability & dissolution.

So Paracetamol alone is a drug & when we add some Excipients with it, it is converted into a dosage form.

There are different types of dosage forms solid dosage form e.g ,solid dosage  liquid dosage form, semi-solid dosage form, parenteral & inhalation dosage forms.

Many drugs are available in more than one dosage form depending on their physicochemical properties & stability data.

Here If we combine solid excipients with paracetamol it will be converted into solid dosage forms e.g. tablets.

Paracetamol+Diluents+Binders+Disintegrants+Lubricants & Glidants.

If we use liquid solvents & suspending agents the paracetamol will be converted into liquid dosage form. 


Pure API is known as a drug & the physical form of a drug in which it is administered is known as the dosage form. In the above examples, paracetamol is a drug or  API & Paracetamol tablets and paracetamol suspension are examples of the dosage form in which it is available.

Read More 

  1. Difference between disintegration & dissolution.
  2. Difference between Validation & Calibration.
  3. Difference Between Wet Granulation & Dry Granulation 
  4. GMP vs cGMP and 21 CFR.