A 75-year-old male patient is a known case of a pulmonary disease and is being treated with inhalational coicosteroids and daily theophylline.The patient was admitted to a hospital for urinary retention few days back and catheterization was done. However, the condition got complicated with urinary tract infection and the patient was put on an antibiotic for the same. Now the patient is presenting with symptoms such as nausea, vomiting, abdominal pain, headache and a fine hand tremor. The patient also appears to have tachycardia. According to the doctor, the symptoms may be due to increased serum levels of the drugs taken by the patient. Which of the following drug may be responsible for the patient's condition?
High-Yield Explanation
Theophylline is metabolized mainly by CYP1A2 hepatic microsomal enzyme. Inhibitors of CYP1A2: Cimetidine Ciprofloxacin Erythromycin Others are: - Aemisinin Atazanavir Enoxacin Ethinyl estradiol Fluvoxamine Furafylline Galangin Mexiletene Tacrine Thiabendazole Zileuton All these drugs inhibit the metabolism of theophylline and therefore may result in its toxicity. Nausea is a common side effect; tachycardia and tremors are also seen. Monitoring of blood theophylline levels is required to minimize toxicity.