A client with overactive bladder starts a new prescription for oxybutynin. When assessing the client prior to medication administration, which finding should the practical nurse (PN) report to the charge nurse?

Choice A reason: A color change during a chemical reaction indicates the formation of new substances with altered molecular structures, affecting light absorption. For instance, iron reacting with oxygen forms iron oxide, shifting from silver to reddish-brown. This reflects a chemical transformation where new compounds with distinct optical properties are produced, confirming a reaction at the molecular level.

Choice B reason: Precipitate formation signifies a chemical reaction as soluble reactants produce an insoluble solid. In a double displacement reaction, such as silver nitrate combining with sodium chloride, silver chloride precipitates. This occurs due to ion exchange, forming a new compound with low solubility, providing visible evidence of a chemical change driven by molecular restructuring.

Choice C reason: Gas release during a reaction indicates a chemical change, as new gaseous products form from reactants. For example, sodium bicarbonate reacting with acetic acid produces carbon dioxide gas. This results from molecular bond rearrangement, where reactants break and reform into new molecules, including a gas, confirming a chemical transformation.

Choice D reason: Temperature changes often accompany chemical reactions, reflecting energy shifts. Exothermic reactions, like combustion, release heat, increasing temperature, while endothermic reactions absorb heat, decreasing it. These changes occur as chemical bonds break and form, redistributing energy. This energy dynamic is a hallmark of chemical reactions, indicating molecular-level transformations.

Choice E reason: This choice is correct as all listed signs—color change, precipitate formation, gas release, and temperature change—are indicators of chemical reactions. Each reflects molecular rearrangements, such as new compound formation or energy shifts. By encompassing all these observable phenomena, this option accurately represents the diverse physical manifestations of chemical changes.

Choice A reason: Montelukast is a leukotriene receptor antagonist that inhibits leukotrienes, mediators of inflammation in allergic responses. By blocking these, it reduces airway inflammation, bronchoconstriction, and mucus production, preventing asthma or allergic rhinitis symptoms. This prophylactic action targets the immune response to allergens, stabilizing respiratory function before symptoms escalate.

Choice B reason: Montelukast does not increase mucus production. Instead, it reduces mucus by inhibiting leukotriene-driven inflammation in the airways. Increased mucus is a symptom of uncontrolled asthma or allergies, which montelukast aims to prevent. This choice is incorrect as it contradicts the drug’s mechanism of reducing inflammatory responses in the lungs.

Choice C reason: Montelukast does not contract respiratory smooth muscles. It prevents bronchoconstriction by blocking leukotrienes, which cause smooth muscle contraction in asthma. By inhibiting this pathway, it promotes airway relaxation, not contraction. This choice is incorrect, as it misrepresents the drug’s role in maintaining open airways.

Choice D reason: Montelukast does not repair damaged lung tissue. Its primary role is to prevent inflammation and bronchoconstriction caused by allergens. Lung tissue repair involves other physiological processes, not influenced by montelukast. This choice is incorrect, as it falsely attributes tissue regeneration to a drug focused on immune modulation.