Important Precautions Precaution on Special Populations Precaution Concerning Dosage & Administration (N/A) Precaution Concerning Use

Important Precautions

(1) Abnormal ejaculation (e.g., retrograde ejaculation) has been reported. Therefore, this drug should be used after obtaining the understanding of patients by carefully explaining the risk of abnormal ejaculation.

(2) Orthostatic hypotension may occur. Therefore, caution should be exercised regarding fluctuations in blood pressure due to changes in body posture.

(3) Dizziness may occur. Therefore, the patient should be advised to exercise caution when engaging in hazardous activities such as working at heights or driving a car.

(4) Prior to commencement of treatment with Silodosin (Urief®) the patient should be asked whether they are taking any hypotensive drugs and, in the event that any hypotensive drug is used, attention should be paid to changes in blood pressure while using Silodosin (Urief®). If a decrease in blood pressure occurs, appropriate therapeutic actions, such as dosage reduction or discontinuation of treatment, should be taken.

(5) It should be borne in mind that treatment with this drug does not eliminate the cause of the disease, but gives symptomatic relief. If treatment with Silodosin (Urief®) does not result in the expected effect, consideration should be given to other appropriate therapeutic measures such as surgery.

(6) Since benign prostatic hyperplasia (BPH) and prostate carcinoma may present the same symptoms and can co-exist, patients thought to have BPH should be examined prior to starting therapy with Silodosin (Urief®), to rule out the presence of carcinoma of the prostate. Digital rectal examination and, when necessary, determination of prostate specific antigen (PSA) should be performed before treatment and at regular intervals afterwards.

(7) This drug is associated with a high incidence of adverse reactions and abnormal ejaculation is reported frequently as a characteristic adverse reaction. Silodosin (Urief®) should be used after careful consideration is given to the risks associated with its use and carefully explaining the adverse reactions to the patient.

(8) It has been reported that intraoperative floppy iris syndrome (IFIS) attributable to α1-blocking effect had been observed in patients who are currently receiving treatment with an α1-blocker, or who have previously received such treatment.

Precautions on Special Populations

Silodosin (Urief®) should he administered with care in the following patients:

  1. Patients with orthostatic hypotension [Symptoms may be aggravated.]
  2. Patients with impaired hepatic function [Elevated plasma drug concentrations may occur.]
  3. Patients with impaired renal function [Elevated plasma drug concentrations have been reported.]
  4. Patients treated with phosphodiesterase-5 inhibitors.
  5. The plasma concentration of silodosin may be elevated in patients with impaired hepatic function. It has been reported that plasma concentration of silodosin is increased in patients with impaired renal function. Therefore, starting treatment at a low dose (2 mg/ dose) while observing the condition of the patient, for instance, should be considered.



The elderly often have reduced physiological function. If hepatic or renal function is reduced, the elderly should be treated while carefully monitoring the condition of the patient, such as start administration at a low dose (2 mg/dose).

Precaution Concerning Use

When this drug is supplied in press-through package (PTP), it should be removed from the PTP sheet for administration. [It was reported that, when PTP sheet was accidentally swallowed by a patient, the hard and sharp edges of the PTP pierced the esophageal mucosa resulting to esophageal perforation, which led to serious complications such as mediastinitis.]