What muscle effect is associated with theophylline toxicity?

The correct answer is associated with tremors, which occur as a significant side effect of theophylline toxicity. Theophylline is a bronchodilator commonly used in treating asthma and other respiratory conditions, and its mechanism involves the inhibition of phosphodiesterase, which leads to increased levels of cyclic AMP. High levels of cyclic AMP can cause stimulation of the central nervous system as well as increased catecholamine release, resulting in symptoms such as tremors.

Tremors are particularly notable because they reflect the drug's effects on the neuromuscular system. This involuntary shaking is typically seen in the hands and can often resemble physiological tremors, which can become exaggerated in the presence of theophylline toxicity. Understanding the mechanism of theophylline and its impact on neuromuscular activity helps clarify why tremors are a key sign of toxicity.

In contrast, options like muscle weakness, increased muscle tone, and muscle cramps may not be specifically representative of theophylline toxicity. This condition is more closely associated with its stimulatory effects rather than producing generalized weakness or increased muscle tone. Additionally, while muscle cramps can happen due to various causes, they are not a classic symptom of theophylline toxicity. Therefore, tremors are the more direct