Active pharmaceutical substances, also known as active pharmaceutical ingredients (APIs), are the components in drugs that produce the intended therapeutic effects. They can be classified in various ways, including their origin, chemical structure or therapeutic use. Here are some common types of APIs:
1. Based on Origin:
- Natural: Derived from plants, animals or microorganisms. Examples include morphine (from poppy plants) and penicillin (from mold).
- Synthetic: Chemically synthesized in laboratories. Examples include aspirin and ibuprofen.
- Semi-Synthetic: Derived from natural sources and modified chemically. Examples include amoxicillin (modified penicillin).
- Biotechnological/Biological: Produced using biotechnology, such as recombinant DNA technology. Examples include insulin, monoclonal antibodies, and vaccines.
2. Based on Chemical Structure:
- Small Molecules: Low molecular weight, typically produced by chemical synthesis. Examples include paracetamol and sildenafil.
- Large Molecules (Biologics): High molecular weight, complex structures, often produced through biological processes. Examples include proteins, peptides, and monoclonal antibodies.
3. Based on Therapeutic Use:
- Antibiotics: For treating bacterial infections. Examples include amoxicillin and ciprofloxacin.
- Analgesics: For pain relief. Examples include paracetamol and ibuprofen.
- Antipyretics: For reducing fever. Examples include acetaminophen.
- Antihypertensives: For managing high blood pressure. Examples include lisinopril and amlodipine.
- Antidiabetics: For managing diabetes. Examples include metformin and insulin.
- Antineoplastics: For cancer treatment. Examples include doxorubicin and paclitaxel.
- Antivirals: For treating viral infections. Examples include acyclovir and remdesivir.
4. Based on Mechanism of Action:
- Enzyme Inhibitors: Inhibit specific enzymes to treat diseases. Examples include ACE inhibitors (lisinopril) and protease inhibitors (ritonavir).
- Receptor Agonists/Antagonists: Target specific receptors to produce effects or block them. Examples include beta-blockers (propranolol) and opioid agonists (morphine).
- Ion Channel Modulators: Affect ion channels to alter cell function. Examples include calcium channel blockers (amlodipine).
5. Based on Dosage Form:
- Solid: Tablets, capsules, powders.
- Liquid: Solutions, suspensions, emulsions.
- Semi-Solid: Creams, gels, ointments.
- Gaseous: Inhalers, anesthetic gases.
These classifications help in understanding how APIs are developed, used and regulated in the pharmaceutical industry.