A hypeensive patient was staed on some anti-hypeensive drug but he developed dry cough. Which of the following drug can be responsible for this effect?
**Core Concept**
The development of a dry cough in a hypertensive patient on antihypertensive medication is a side effect associated with certain classes of drugs that affect the renin-angiotensin-aldosterone system (RAAS). This system plays a crucial role in regulating blood pressure and electrolyte balance.
**Why the Correct Answer is Right**
The correct answer is related to drugs that block the action of angiotensin II, a potent vasoconstrictor that increases blood pressure. By inhibiting the effects of angiotensin II, these drugs reduce peripheral resistance and lower blood pressure. However, they can also cause a dry cough due to the accumulation of bradykinin, a peptide that stimulates cough receptors in the lung. This is because these drugs also inhibit the breakdown of bradykinin by angiotensin-converting enzyme (ACE), a key enzyme involved in the RAAS pathway.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option does not provide a plausible explanation for the development of a dry cough in a hypertensive patient.
* **Option B:** This option is incorrect because it is not directly related to the RAAS pathway or the development of a dry cough.
* **Option D:** This option is incorrect because it does not accurately describe a class of drugs that can cause a dry cough.
**Clinical Pearl / High-Yield Fact**
The dry cough associated with ACE inhibitors can be mitigated by switching to an angiotensin receptor blocker (ARB), which targets the same pathway but does not inhibit ACE.
**Correct Answer:** C.