Tamsumax Warnings

The signs and symptoms of orthostasis (postural hypotension, dizziness and vertigo) were detected more frequently in Tamsulosin HCl (Tamsumax) capsule-treated patients than in placebo recipients. As with other alpha-adrenergic blocking agents there is a potential risk of syncope.
Patients beginning treatment with Tamsulosin HCl (Tamsumax) capsules should be cautioned to avoid situations where injury could result should syncope occur.
Doses of Tamsulosin HCl (Tamsumax) higher than 0.4 mg (e.g., 0.8 mg) should not be used in combination with strong inhibitors of CYP3A4 (e.g., ketoconazole).
Rarely (probably less than 1 in 50,000 patients), tamsulosin, like other alpha-1 antagonists, has been associated with priapism (persistent painful penile erection unrelated to sexual activity). Because this condition can lead to permanent impotence if not properly treated, patients must be advised about the seriousness of the condition.