A nurse is caring for a client who is receiving neostigmine. Which of the following manifestations should the nurse identify as an adverse reaction to the medication? (Select all that apply.)

Furosemide, a loop diuretic, is known to cause orthostatic hypotension as an adverse effect. It works by increasing urine output and reducing fluid volume, which can lead to a decrease in blood pressure when standing up, causing dizziness or lightheadedness.

Dabigatran (A) is an anticoagulant used to prevent blood clots and does not typically cause orthostatic hypotension as a side effect.

Levothyroxine (B) is a thyroid hormone replacement medication used to treat hypothyroidism. It does not usually cause orthostatic hypotension.

Isoproterenol (C) is a non-selective beta-adrenergic agonist that is primarily used for cardiac stimulation. It can cause tachycardia and palpitations, but orthostatic hypotension is not a common side effect.

Neostigmine is a medication classified as an acetylcholinesterase inhibitor. It is commonly used to treat myasthenia gravis and to reverse the effects of non-depolarizing neuromuscular blocking agents used during surgery. Adverse reactions to neostigmine are related to its cholinergic effects, which result from increased acetylcholine levels in the body.

Let's go through the options:

A. Hypoactive bowel sounds: Neostigmine can actually increase gastrointestinal motility and may cause increased bowel sounds or even diarrhea, not hypoactive bowel sounds. Therefore, hypoactive bowel sounds are not an adverse reaction to neostigmine.

B. Sweating: Sweating is a cholinergic effect and can be an adverse reaction to neostigmine. Increased sweating is a common sign of cholinergic stimulation.

C. Respiratory distress: Respiratory distress can occur as an adverse reaction to neostigmine, particularly if the client has a history of asthma or other respiratory conditions. Neostigmine can cause bronchoconstriction and excessive secretions, leading to respiratory distress.

D. Urinary retention: Neostigmine is actually used to treat urinary retention by increasing bladder contraction. Therefore, urinary retention is not an adverse reaction to neostigmine.

E. Bradycardia: Bradycardia (slow heart rate) is a significant adverse reaction to neostigmine due to its cholinergic effects on the heart. Increased acetylcholine levels can lead to excessive stimulation of the vagus nerve, resulting in bradycardia.