What are the side effects of Flomax (Tamsulosin)?

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From the Guidelines

Flomaxtra (tamsulosin hydrochloride) commonly causes side effects including dizziness, lightheadedness, headache, retrograde ejaculation, and nasal congestion, as reported in the most recent study 1. The side effects of Flomaxtra are primarily due to its mechanism of action, which involves relaxing smooth muscles in the prostate and bladder neck to improve urine flow.

  • Common side effects include:
    • Dizziness
    • Lightheadedness
    • Headache
    • Retrograde ejaculation (reduced or no semen during orgasm)
    • Nasal congestion
  • Less common side effects include:
    • Nausea
    • Diarrhea
    • Constipation
    • Skin rash
  • Serious but rare side effects include:
    • Priapism (prolonged erection)
    • Fainting
    • Allergic reactions It is essential to take the first dose of Flomaxtra at bedtime to minimize dizziness, avoid driving until you know how it affects you, and stand up slowly to prevent falls, as recommended by the 2023 European Association of Urology guidelines 1. If you experience severe dizziness, fainting, or any allergic reactions, contact your doctor immediately. Most side effects are mild and may diminish as your body adjusts to the medication, typically within a few weeks of starting treatment, as noted in the study by Nickel et al. [@31@].

From the FDA Drug Label

In an open-label, 12-month safety study, 87 patients were treated with tamsulosin hydrochloride. The most frequently reported adverse events (<5%) from the pooled data of both studies were urinary tract infection, vomiting, pyrexia, headache, nasopharyngitis, cough, pharyngitis, influenza, diarrhea, abdominal pain, and constipation.

The side effects of FLOMAXTRA (tamsulosin) include:

  • Urinary tract infection
  • Vomiting
  • Pyrexia
  • Headache
  • Nasopharyngitis
  • Cough
  • Pharyngitis
  • Influenza
  • Diarrhea
  • Abdominal pain
  • Constipation 2

From the Research

FLOMAXTRA Side Effects

  • FLOMAXTRA, also known as tamsulosin, is a medication used to treat benign prostatic hyperplasia (BPH) and has been studied for its efficacy and tolerability in various clinical trials 3.
  • The side effect profile of tamsulosin has been compared to other alpha1-adrenoceptor antagonists, such as alfuzosin, terazosin, and doxazosin, with studies suggesting that tamsulosin may be better tolerated than some of these alternatives 3.
  • Common side effects associated with tamsulosin include dizziness, orthostatic hypotension, and hypotension, with one study finding that the incidence of hypotension was higher for tamsulosin than for 5-alpha reductase inhibitors (5ARIs) 4.
  • The risk of severe hypotension has been found to be increased during the first eight weeks after initiating tamsulosin treatment, as well as after restarting treatment, highlighting the importance of careful patient counseling and monitoring 4.
  • Orthostatic hypotension, a potential side effect of tamsulosin, can be managed through nonpharmacologic and pharmacologic measures, including volume expansion, sympathetic enhancement, and avoiding the supine position 5, 6, 7.

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Professional Medical Disclaimer

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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