<prompt> All of the following are true about staing betablocker therapy in cases of CHF, ExceptThey should be initiated at the effective dosesThey should be gradually increased over weeksSpecial precautions should be taken in NYHA class III IVCarvedilol and Metoprolol are the preferred drugs  <response>: Answer is A They should be initiated at the effective doses Beta blocker should be initiated at lower than effective doses in CHF Beta blockers should be initiated at lower than effective doses in CHF and be Beta blockers should be initiated at low doses followed by gradual increments in the dose if lower doses have been well tolerated. The dose of beta blockers should be increased until the doses used are similar to those that have been repoed effective in clinical trials. The titration of beta blockers should proceed no more rapidly than at 2 week intervals because the initiation and or increased dosing of these agents may lead to worsening fluid retention -- Harrisons 17th1450 Special precaution should be taken in NYHA class III IV Although data suggests that patients with NYHA class IHB and IV CHF may tolerate beta blockers and benefit from their use, this group of patients should be approached with considerable caution --Goodman Gillmans Manual of Pharmacology 2007570 Carvedilol and Metoprolol are the preferred beta blockers in CHF Non selective third generation beta blockers Bucindolol, Carvedilol as well a the Beta-I selective agent Metoprolol are generally well tolerated by patients with CHF. -Current Diagnosis Treatment in Cardiology 3,1217 