Which adverse effect is commonly associated with Methylxanthines besides tachydysrhythmias?

Methylxanthines, which include drugs such as theophylline, are known to have a range of potential side effects as they act as bronchodilators by relaxing the smooth muscles of the airways. One of the common side effects associated with their use is gastrointestinal upset. This can manifest as nausea, vomiting, or general discomfort in the gastrointestinal tract.

The mechanism behind this gastrointestinal upset may be related to the way methylxanthines stimulate the central nervous system and increase gastric acid secretion, leading to discomfort. While weight loss and skin rash can occasionally occur, they are not commonly reported or directly linked to the most prevalent side effects of methylxanthines. Cardiac arrest, while a serious condition, is not typically a direct result of methylxanthine use in the dosage used for asthma management, rather tachydysrhythmias are more prevalent due to their stimulating effects on the heart. Thus, gastrointestinal upset stands out as a well-recognized and common adverse effect associated with methylxanthines.