Tag: Narrow therapeutic index

Tacrolimus has a narrow therapeutic range, which means the blood level needs to be carefully maintained to be effective without causing toxicity. This is why there is no single answer to what is a normal tacrolimus level; the target is highly individualized based on the organ transplant and time since surgery.

According to StatPearls, acetaminophen toxicity is the leading cause of liver failure in the United States, highlighting the serious risk posed even by common over-the-counter drugs. Understanding **what drugs cause toxicity** is crucial for preventing adverse health outcomes, as effects can range from mild side effects to life-threatening organ damage.

Derived from the autumn crocus, colchicine has a history spanning thousands of years, with therapeutic use documented since ancient Egypt. Despite this long history and proven efficacy for inflammatory conditions like gout and pericarditis, colchicine is often less preferred by clinicians today due to significant safety concerns and its narrow therapeutic index.

Prescriptions for digoxin in the US fell by nearly 90% between 1997 and 2012, marking a significant shift in cardiac care. This dramatic decline is rooted in critical safety concerns and the rise of newer, superior treatments, explaining why is digoxin no longer prescribed as a first-line therapy.

According to the American Journal of Cardiology, digoxin toxicity remains a common and serious public health problem, despite a decline in its overall use. The major problem with digoxin is its exceptionally narrow therapeutic index, meaning the difference between a safe and effective dose and a toxic, potentially fatal dose is very small. This fine line necessitates vigilant monitoring and makes the drug's management complex for clinicians.

Over 20 million Americans are estimated to be on levothyroxine, making it one of the most prescribed drugs in the country. Despite its widespread use, many patients wonder: Is levothyroxine a high risk drug? The answer lies not in its inherent danger, but in its narrow therapeutic index, meaning small dosage changes can have significant effects.

Adverse drug events (ADEs) lead to an estimated 280,000 hospital admissions in the U.S. annually, with a significant portion involving high-risk medications [1.4.7]. So, **what is a high risk drug?** They are medications with a heightened potential to cause significant patient harm if used in error [1.2.3, 1.6.5].

Adverse drug reactions are a significant cause of injury and death, underscoring the fine line between a medication's therapeutic benefit and its potential for harm [1.3.4]. The question of *which drug is highly toxic* is complex, as toxicity depends on the drug's properties, the dose administered, and individual patient factors [1.3.1].

Over 46,000 organ transplants were performed in the US in 2023, with many patients requiring the potent immunosuppressant tacrolimus to prevent rejection. Despite its effectiveness, understanding **why tacrolimus is high risk** is crucial due to its narrow therapeutic index and a wide range of severe side effects.