Zochek 10 mg tablets should not be given to patients with severe renal impairment (creatinine clearance < 30 ml/min) in view of the lack of clinical safety data in this group of patients.
Alfuzosin should be given with caution to patients who are on antihypertensive medication or nitrates.
In some subjects postural hypotension may develop, with or without symptoms (dizziness, fatigue, sweating) within a few hours following administration. In such cases, the patient should lie down until the symptoms have completely disappeared.
These effects are usually transient, occur in the beginning of treatment and do not usually prevent the continuation of treatment.
Pronounced drop in blood pressure has been reported in post-marketing surveillance in patients with pre-existing risk factors (such as underlying cardiac diseases and/or concomitant treatment with anti-hypertensive medication). The risk of developing hypotension and related adverse reactions may be greater in elderly patients.
Care should be taken when alfuzosin is administered to patients who have had a pronounced hypotensive response to another alpha1-blocker.
In coronary patients, the specific treatment for coronary insufficiency should be continued. If angina pectoris reappears or worsens, alfuzosin should be discontinued.
As with all alpha-1-blockers, alfuzosin should be used with caution in patients with acute cardiac failure.
Patients with congenital QTc prolongation, with a known history of acquired QTc prolongation or who are taking drugs known to increase the QTc interval should be evaluated before and during the administration of alfuzosin
Concomitant use of alfuzosin and potent CYP3A4 inhibitors (such as itraconazole, ketoconazole, protease inhibitors, clarithromycin, telithromycin and nefazodone) should be avoided (see section 4.5). Alfuzosin should not be used concomitantly with CYP3A4 inhibitors that are known to increase the QTc interval (e.g. itraconazole and clarithromycin) and a temporary interruption of alfuzosin treatment is recommended if treatment with such medicinal products is initiated.
The 'Interoperative Floppy Iris Syndrome' (IFIS, a variant of small pupil syndrome) has been observed during cataract surgery in some patients on or previously treated with tamsulosin. Isolated reports have also been received with other alpha-1 blockers and the possibility of a class effect cannot be excluded. As IFIS may lead to increased procedural complications during the cataract operation, current or past use of alpha-1 blockers should be made known to the opthalmic surgeon in advance of surgery.
Alfuzosin, like other alpha adrenergic antagonist, has been associated with priapism (persistent painful penile erection unrelated to sexual activity; see section 4.8). Because this condition can lead to permanent impotence if not properly treated, patients should be advised to seek immediate assistance in the event of an erection that persists longer than 4 hours.
Patients should be warned that the tablet should be swallowed whole. Any other mode of administration, such as crunching, crushing, chewing, grinding or pounding to powder should be prohibited. These actions may lead to inappropriate release and absorption of the drug and therefore possible early adverse reactions.