Medicinal products are used for the prophylaxis or management of diseases. It brings about the purpose of affecting body function or is used to make a medical diagnosis.
Sources of Drugs
- Plants were the primary sources in earlier times.
- Later, minerals and substances of animal origin were used.
- Nowadays, pharmaceutical drugs are manufactured synthetically or semisynthetically.
Drugs to Medicinal Products
- Nowadays, there is a lot of emphasis on the potency and purity of APIs (active pharmaceutical ingredients).
- Just imagine, if provided in raw form, patients may have great difficulty to withdraw the correct amount of medicines.
- Besides, other challenges are sterile conditions requirement and correct methods of drug extraction.
To counter these challenges, the formulation process ensures drugs to be converted into medicines. A pharmacist is skilled enough to extract the API and compound it for patients. With changing times, the role of the pharmacist role has evolved as
- conducting activities relating to drug formulation
- Discovery of new molecules
- Testing APIs for efficacy and safety
- Providing pharmaceutical care in hospital and community pharmacy
Administration of Medicines
- When drugs are administered, it causes cellular changes, followed by physiological changes. This is known as a drug effect.
- The ‘rights’ of drug administration: right medicine at the right dose, in the right form to the right patient, at the right time, by the right route, using the right technique, and maintain the right documentation
- time-consuming, complex and expensive process
- for appropriate dosage form, every drug needs to undergo pre-formulation studies and formulation development
- Pre-formulation Studies investigate the physical and chemical properties of a drug including:
- solubility and dissolution rates
- chemical stability
- melting point
- particle morphology
2. Formulation Development: concentrates on the desired final dosage form
Drug Effects can be subdivided into:
- Systemic Effect (e.g. tablets): drug is distributed throughout the body to cause a physiological effect
- Local Effect (e.g. nose drops): drug is applied locally, where it is needed. for example,
- IV is preferred in emergency cases where fast action is desired.
- In asthma, bronchodilators and corticosteroids are used as inhalers to reduce side-effects
- Gentamicin has the best absorption qualities when used parenterally
- Insulin in injectables only considering it degrades in the GI tract.