I take 25 mg. of hydrochlorothiazide daily and I don't notice any difference, for better or for worse. But this is a very mild diuretic in a very low dose.
Here is additional meds info from drugstore.com. You'll notice that erectile dysfunction is associated with a number of BP meds:
Can blood pressure medicines cause impotence?
Impotence, or erectile dysfunction (ED), can result from many medical conditions including high blood pressure, diabetes, and heart disease. Several different types of medications, including those for high blood pressure, can also cause it. As with most side effects, ED is more common with higher doses of medication. Changing to a different drug may solve the problem.
Some diuretics and beta-blockers are more likely to cause ED. As many as 25 to 50 percent of men who take the diuretics
chlorothiazide (brand name Diuril), hydrochlorothiazide (Hydrodiuril), and
spironolactone (Aldactone), or the beta blocker
propranolol (Inderal), are affected. Other beta-blockers, such as
atenolol (Tenormin) and
metoprolol (Lopressor) cause this side effect in only 1 to 2 percent of men who take them.
Other types of blood pressure drugs rarely cause ED. Less than 1 percent of men who take the following drugs report the problem: Angiotensin converting enzyme (ACE) inhibitors such as
benazepril (Lotensin),
enalapril (Vasotec), and
lisinopril (Prinivil, Zestril)
Calcium channel blockers such as
amlodipine (Norvasc),
diltiazem (Cardizem), and
nifedipine (Procardia)
Loop diuretics such as
furosemide (Lasix)
Alpha blockers such as
prazosin (Minipress) and
doxazosin (Cardura) Talk to your doctor if you experience impotence while on a blood pressure medication. Adjusting your dose or switching to a different medicine may make a tremendous difference.