Tadalafil Nitrates

Sildenafil and vardenafil decrease systolic/diastolic blood pressure by 8 to 10/5 to 6 mm Hg for 1 to 4 hours after a dose. Although most patients are asymptomatic, multiple antihypertensives, nitrates, and baseline hypotension increase the risk of developing adverse effects. Although tadalafil does not decrease blood pressure, it should be used with caution in patients with cardiovascular disease because of the inherent risk associated with sexual activity. 

Drugs that may interact with nitrates include alcohol, alteplase, aspirin, beta-blockers, calcium channel blockers, dihydroergotamine, heparin, nondepolarizing muscle relaxants, phenothiazines, phosphodiesterase inhibitors (eg, sildenafil, tadalafil, vardenafil), and vasodilators. 

Flypersensitivity to any component of the tablet administration with nitrates (either regularly and/or intermittently) and nitric oxide donors because of the potentiation of hypotension (see Drug Interactions) coadministration with alpha-blockers (vardenafil only) coadministration with alpha-blockers other than 0.4 mg/day tamsulosin (tadalafil only). 

Isosorbide Dinitrate Hydralazine (BiDil) [Antianginal, Antihypertensive/Vasodilator, Nitrate] Uses HF in African Amer-icans improve survival functional status, prolong time between hospitalizations Action Relaxes vascular smooth muscle peripheral vasodilator Dose Initially 1 tab tid PO (if not tol ated reduce to 1/2 tab tid), titrate >3-5 d as tolerated Max 2 tabs tid Caution [C, /-] recent MI, syncope, hypovolemia, hypotension, hep impair Contra For children, concomitant use w/ PDE5 inhibitors (sildenafil) Disp Tabs SE HA, dizziness, orthostatic hypotension, sinusitis, GI distress, tach, paresthesia, amblyopia Interactions t Risk of severe hypotension W/ antihypertensives, ASA, CCBs, MAOIs, phenothiazides, sildenafil, tadalafil, vardenafil, EtOH X pressor response Wf i -1- effects W7 NSAIDs EMS Use ASA, antihypertensives and CCBs w/ caution, may t hypotension concurrent Viagra-type drug use can lead to profound hypotension concurrent EtOH use can t effects OD May cause N/V, profound hypotension, skin flushing, HA from ICP, bradycardia, confusion, and circulatory collapse activated charcoal may be effective, epi use is contraindicated... 

Avoid using nitrate drugs and alpha-adrenergicblockers concurrently with tadalafil... 

Kloner FtA, Hutter AM, Emmick JT, et al. Time course of the interaction between tadalafil and nitrates. J Am Coll Cardiol 2004 42 1855-1860. 

Squill 1. Sildenafil 2. Tadalafil 3. Vardenafil t blood levels of the drug, leading to serious vasodilatation. T risk of cardiac arrhythmia Inhibits CYP3A4, which metabolizes these drugs (grapefruit juice) Unknown mechanism (squill) Avoid concomitant use. Avoid the combination of grapefruit juice and nitrates with these medications... 

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