Should I stop finasteride or tamsulosin for hypotension?

From the Guidelines

If you're experiencing hypotension while taking finasteride and tamsulosin, your healthcare provider is likely to recommend stopping or adjusting tamsulosin before considering changes to finasteride, due to tamsulosin's higher likelihood of causing hypotension. Tamsulosin is an alpha-blocker that relaxes blood vessels and the muscles in the prostate and bladder neck, which can lead to a decrease in blood pressure, particularly when starting the medication or increasing the dose 1. Symptoms of hypotension may include dizziness, lightheadedness, or fainting, especially when standing up quickly. Finasteride, on the other hand, works by blocking the conversion of testosterone to dihydrotestosterone to shrink the prostate and rarely causes significant blood pressure changes.

According to the 2021 AUA guideline, alpha blockers like tamsulosin are effective in treating lower urinary tract symptoms (LUTS) attributed to benign prostatic hyperplasia (BPH), but the choice of alpha blocker should be based on patient age and comorbidities, as well as different adverse event profiles, such as ejaculatory dysfunction and changes in blood pressure 1. The guideline recommends offering one of the following alpha blockers as a treatment option for patients with bothersome, moderate to severe LUTS/BPH: alfuzosin, doxazosin, silodosin, tamsulosin, or terazosin.

Some key points to consider when managing hypotension in patients taking tamsulosin include:

• Tamsulosin has a higher probability of causing ejaculatory dysfunction but a lower probability of orthostatic hypotension compared to other alpha blockers 1
• The primary adverse events reported with alpha-blocker therapy are orthostatic hypotension, dizziness, tiredness, ejaculatory problems, and nasal congestion 1
• Patients with hypertension may require separate management of their hypertension, as alpha blockers may not provide optimal management of concomitant hypertension 1

Your doctor may recommend temporarily stopping tamsulosin, adjusting the dosage, or taking it at bedtime to minimize hypotensive effects. They may also check for other causes of hypotension or potential drug interactions. Never stop prescription medications without medical guidance, as sudden discontinuation could worsen your underlying prostate condition.

From the FDA Drug Label

The signs and symptoms of orthostasis (postural hypotension, dizziness, and vertigo) were detected more frequently in Tamsulosin Hydrochloride Capsules -treated patients than in placebo recipients. Caution is advised when alpha adrenergic blocking agents, including Tamsulosin Hydrochloride Capsules, are co-administered with PDE5 inhibitors. Alpha-adrenergic blockers and PDE5 inhibitors are both vasodilators that can lower blood pressure. Concomitant use of these two drug classes can potentially cause symptomatic hypotension

Hypotension is a potential side effect of tamsulosin.

• Tamsulosin can cause orthostatic hypotension, and its use with other vasodilators like PDE5 inhibitors can increase this risk.
• There is no direct information in the provided drug labels about finasteride causing hypotension.
• It is recommended to exercise caution when using tamsulosin, especially in combination with other medications that can lower blood pressure.
• If you are experiencing hypotension, it is recommended to consult your doctor about the best course of action, which may include stopping or adjusting the dose of tamsulosin 2, 2, 2.

From the Research

Hypotension and Medication

When considering the management of hypotension in relation to medications like finasteride and tamsulosin, it's essential to understand the pharmacological profiles of these drugs.

• Finasteride is a 5alpha-reductase inhibitor used primarily for the treatment of benign prostatic hyperplasia (BPH) and androgenetic alopecia.
• Tamsulosin is an alpha(1A)- and alpha(1D)-adrenoceptor antagonist, which is selective for the prostate gland, making it effective for treating lower urinary tract symptoms (LUTS) associated with BPH.

Effects on Blood Pressure

The decision to stop either finasteride or tamsulosin due to hypotension should be based on their respective effects on blood pressure:

• Tamsulosin has been shown to have minimal effects on blood pressure in most patients 3, 4, 5. It is considered to have a low potential for causing hypotensive effects compared to other alpha(1)-adrenoceptor antagonists 3, 6.
• Finasteride does not directly affect blood pressure as its mechanism of action involves inhibiting the conversion of testosterone to dihydrotestosterone, which is primarily related to prostate size reduction and not directly to vascular tone or blood pressure regulation.

Considerations for Hypotension

Given the information:

• If hypotension is a concern, tamsulosin might still be considered safer in terms of blood pressure effects compared to other alpha-blockers, but its combination with other medications, like sildenafil, can lead to pronounced hypotension in susceptible patients 7.
• Finasteride does not have a direct impact on blood pressure, suggesting that it might not be the primary culprit in cases of hypotension.

Clinical Decision

The clinical decision to stop either medication should be based on the individual patient's response and the severity of hypotension. Since tamsulosin has a more direct mechanism that could potentially influence blood pressure, especially in combination with other drugs, monitoring its effects closely is crucial. However, given its selective action and generally favorable profile regarding blood pressure, stopping tamsulosin solely due to concerns about hypotension might not be necessary unless there are specific patient factors or combinations with other medications that significantly increase this risk 7, 4, 6.