Drug intolerance

If someone has a very low MTC for a drug, they are likely to experience adverse effects at drug concentrations lower than what it would take to produce the same adverse effects in the general populace; thus, the individual will experience significant toxicity at a dose that is otherwise considered "normal" for the average person.

Variations in MTC can occur at any point in the ADME (absorption, distribution, metabolism, and excretion) process.

While most individuals will possess the effective metabolizing machinery, a person with a defect will have a difficult time trying to clear the drug from their system.

Thus, the drug will accumulate within the blood to higher-than-expected concentrations, reaching a MTC at a dose that would otherwise be considered normal for the average person.

Symptoms include chronic rhinosinusitis with nasal polyps, asthma, gastrointestinal ulcers, angioedema, and urticaria.