What is the dose of Flomax (tamsulosin) for post-operative urinary retention?

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From the FDA Drug Label

Tamsulosin Hydrochloride Capsules 0.4 mg once daily is recommended as the dose for the treatment of the signs and symptoms of BPH. The FDA drug label does not answer the question.

From the Research

For post-operative urinary retention, the standard dose of Flomax (tamsulosin) is 0.4 mg taken once daily, preferably at the same time each day, as recommended by the most recent and highest quality study 1. The medication should be taken approximately 30 minutes after the same meal each day with a full glass of water. If this dose is not effective after 2-4 weeks, it can be increased to 0.8 mg once daily. Patients should be aware that Flomax may cause dizziness or lightheadedness, especially when standing up quickly, so caution is advised when starting the medication. The drug works by relaxing the smooth muscles in the prostate and bladder neck, which helps improve urine flow by reducing the blockage. This is particularly helpful after surgery when swelling and inflammation can contribute to urinary retention. Some key points to consider when managing post-operative urinary retention include:

  • Identifying patients at increased risk of post-operative urinary retention, such as those undergoing certain surgical procedures or with advancing age 2
  • Using conservative measures to help the patient pass urine, and considering pharmacological treatment if necessary 3
  • Being aware of the risk factors for urinary catheterization, such as spinal anesthesia, longer surgery time, and older age 4 Patients should continue taking the medication as prescribed even if symptoms improve, and should not stop without consulting their healthcare provider. It's essential to note that Flomax may take several days to reach its full effect, so patience is needed when starting treatment, and the medication has been shown to be effective in patients with mild to severe lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH) 5.

References

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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