Categorization of Drug Toxicity
Most Adverse Drug reactions are related to dose. Dose-related reactions are usually predictable, and those unrelated to dose are usually unpredictable.
Side effects are Pharmacologic effect, which occurs even when taking normal dosage schedule.
Diarrhea is a common side effect in persons taking oral antibiotics due to killing of normal micro-flora of Gastro-intestinal tract in addition to killing pathogenic bacteria.
Toxicity, which occurs due to over dosage of the drug higher than the therapeutic range for a particular patient.
The severity of the toxicity is usually dose-related.
Toxicity may result from decrease in drug clearance in patients with impaired renal clearance.
Drug allergies are mostly common which is not dosage related, Toxicity is not related to dosage, drug allergy may cause serious toxicity.