Darren asked
I’m a 43 year old man and I have started taking Tamulosin 0.4 two week’s ago for enlarged prostate/tight muscle around neck of bladder. I have noticed very little benefit in terms of urine flow but I seem to be getting more side effects as time goes on. Currently I’m feeling very shaky (chills), blurted vision, and nausea with occasional bouts of feeling lightheaded though not faint.
I am due to see my urologist for a follow up appointment in 5 weeks but do you have any advice in the meantime please?
Answer
Tamsulosin (Flomax) is a common treatment for benign prostatic hyperplasia (BPH). Due to its mechanism of action, tamsulosin can also cause side effects like low blood pressure, dizziness, headache, and nausea. It is important to follow-up with your urologist as soon as possible to prevent worsening of side effects. Below we will discuss more information regarding tamsulosin, including potential ways to lessen the side effects.
The first way to lessen the side effects is to ensure that tamsulosin is being taken approximately 30 minutes after the same meal each day. Taking the medication with food decreases the amount absorbed and should lessen the side effects. It also may be best to take after your last meal if you are experiencing side effects during the day. This should help if having to constantly urinate during the night is a problem.
The next way to lessen the side effects from tamsulosin is to be careful of orthostatic hypotension. Orthostatic hypotension is when your blood pressure drops significantly upon standing up. This can cause some of the symptoms you described like blurred vision and lightheadedness. The best way to prevent orthostatic hypotension is to always take your time when standing up. It is recommended to sit up prior to standing up followed by standing up slowly while holding on to something.
Finally, it may be important to monitor your blood pressure during this time to monitor for low blood pressure. Making sure to drink enough water, avoid standing for long periods of time, and avoid overheating may help prevent dizziness.
How Tamsulosin Works
Tamsulosin is a drug in the class known as alpha-blockers which is primarily used for BPH. Tamsulosin works by inhibiting the alpha-1 receptor which is abundant in prostate and bladder neck muscles. By blocking this receptor, tamsulosin causes relaxation of the muscle tone which allows for improvement of urine flow and other BPH symptoms.
Although tamsulosin is not FDA approved for treatment of
blood pressure, it can cause a drop in blood pressure—although this is less likely to occur relative to
other alpha-blockers such as terazosin and doxazosin. These effects happen with alpha-blockers
because alpha receptors are also located in vascular system and blocking the alpha
effect causes vasodilation.
Source: Flomax
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