**Core Concept**
Theophylline is a methylxanthine derivative used in the management of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). It acts as a phosphodiesterase inhibitor, increasing intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), which leads to bronchodilation, smooth muscle relaxation, and increased diaphragmatic contractility.

**Why the Correct Answer is Right**
Theophylline overdose can cause severe cardiac and neurological toxicity. The mechanism involves the inhibition of adenosine receptors, leading to increased adenosine levels, which in turn cause cardiac arrhythmias, including ventricular tachycardia and fibrillation. Additionally, theophylline competes with caffeine for binding to the adenosine receptor, further exacerbating the cardiac effects.

**Why Each Wrong Option is Incorrect**
**Option A:**
This option is incorrect because theophylline overdose is not primarily associated with gastrointestinal symptoms such as nausea and vomiting.

**Option B:**
This option is incorrect because theophylline overdose does not typically cause significant renal impairment or electrolyte imbalances.

**Option C:**
This option is incorrect because theophylline overdose is not primarily associated with hepatic enzyme induction or altered drug metabolism.

**Clinical Pearl / High-Yield Fact**
In the event of a theophylline overdose, it is essential to perform a thorough cardiac evaluation, including ECG monitoring and cardiac enzyme assessment, to identify potential cardiac toxicity.

**Correct Answer:** C. Seizures, ventricular arrhythmias, and cardiac arrest.