Benign Prostatic Hyperplasia: Causes, Symptoms & Treatment

Benign prostatic hyperplasia, commonly called BPH, is a noncancerous enlargement of the prostate gland that gradually squeezes the urethra and disrupts normal urination. It affects most men as they age, with the global number of cases in men over 60 reaching roughly 79 million by 2019 and the peak burden falling in the 65-to-69 age group.¹ The condition is driven primarily by hormonal changes that accumulate over decades, and its symptoms range from mildly annoying to seriously debilitating. Treatment options now span watchful waiting, daily pills, office-based procedures, and full surgery, so matching the right approach to the right patient is where most of the complexity lies.

How Common Is BPH and Who Gets It

BPH is rare before age 40, but after that it becomes increasingly likely with every passing decade. The condition’s prevalence, incidence, and overall health burden are concentrated in men over 40, with the highest absolute number of cases globally in the 65-to-69 age range.² Between 1990 and 2019, global prevalent cases more than doubled, driven partly by population aging and partly by better detection.¹

There is an interesting disconnect between what pathologists find and what men actually experience. On autopsy, the proportion of prostates showing hyperplastic tissue keeps rising into the 80s and 90s. But in community-based studies that rely on symptoms and clinical prostate enlargement, the peak age-specific prevalence lands around 75 to 79, after which men may die of other causes or stop seeking care for urinary problems.³ In other words, almost every man who lives long enough will develop some degree of prostatic enlargement, but the number who seek help for it peaks in late middle age.

Family history matters, too. Research on men who underwent prostate surgery for BPH at a young age found that their male relatives had a roughly four-fold increase in the risk of needing the same surgery compared to relatives of unaffected men. Brothers of early-onset cases faced a six-fold increase. Segregation analysis suggested a dominant gene associated with early-onset BPH, making family history a meaningful risk factor.⁴

Why the Prostate Keeps Growing

The prostate depends on androgens to develop and maintain itself. In adults, the key driver of prostatic growth is dihydrotestosterone, or DHT, a potent metabolite made when an enzyme called 5-alpha reductase converts testosterone inside prostate tissue. DHT binds to androgen receptors in prostate cells and switches on genes that promote cell growth. During youth this is harmless, but in later decades the accumulated stimulation tips from maintenance into pathologic overgrowth.⁵ This understanding is what led to the development of drugs that block DHT production, which remain among the only treatments that actually shrink the gland rather than just easing symptoms.

Hormones are not the whole story, though. Metabolic syndrome, the cluster of conditions including high blood pressure, elevated blood sugar, excess abdominal fat, and abnormal cholesterol, appears to accelerate prostate growth through inflammation and altered hormone signaling. In a large prospective cohort, researchers found that inflammation markers, liver function, kidney function, and red-blood-cell biomarkers partly mediated the link between metabolic syndrome and BPH risk.⁶ Separately, studies have found that the inflammatory molecule TNF-alpha is associated with both larger prostate volume and a higher rate of newly diagnosed BPH over a four-year follow-up.⁷ The takeaway is that BPH is not purely an “old man’s hormone problem.” Metabolic health, body composition, and chronic low-grade inflammation all feed into it.

What BPH Symptoms Feel Like

Men with BPH experience what doctors broadly call lower urinary tract symptoms, or LUTS. These fall into two main buckets that often overlap in the same person.⁸

Voiding symptoms: A weak or intermittent stream, straining to start, hesitancy, dribbling at the end, and the feeling that the bladder hasn’t fully emptied. These come from the enlarged prostate physically squeezing the urethra.
Storage symptoms: Needing to urinate more frequently during the day, waking up at night to go (nocturia), sudden urgency, and sometimes urgency incontinence. These reflect changes in how the bladder itself behaves after working against chronic obstruction.

Storage symptoms deserve special attention because they tend to bother men most. Nocturia in particular has a strong negative impact on sleep quality, and the effect worsens with each additional episode per night.⁹ A man who gets up three times a night is not just tired; he is at higher risk for falls, daytime drowsiness, mood changes, and reduced quality of life. This is why a thorough evaluation should assess both symptom categories and their severity, since the treatment approach can differ depending on which type dominates.¹⁰

Getting Diagnosed

BPH evaluation typically starts with a symptom questionnaire called the International Prostate Symptom Score, which asks about seven urinary complaints and rates them on a scale. A digital rectal exam checks prostate size and texture, and a uroflowmetry test measures how fast urine flows. In many clinical settings, doctors combine the symptom score with peak flow rate and post-void residual volume to gauge severity. A high symptom score combined with a peak flow below about 10 milliliters per second was found in a large share of patients who went on to benefit from surgery, though no noninvasive combination perfectly predicts urinary obstruction on its own.¹¹

A blood test for prostate-specific antigen (PSA) is often ordered as well, less to diagnose BPH than to help rule out prostate cancer, since both conditions can elevate PSA. The relationship between BPH and cancer is addressed later in this article.

Medications for BPH

Drug therapy is the first-line option for most men whose symptoms are moderate but not yet severe enough for a procedure. Two main drug classes do very different things.

Alpha-blockers, like tamsulosin, work by relaxing smooth muscle in the prostate and bladder neck. This reduces the “dynamic” component of urinary obstruction, meaning the part caused by muscle tension rather than by tissue bulk. The result is usually a noticeable improvement in urine flow within days to weeks.¹² Because they also relax smooth muscle elsewhere, alpha-blockers can cause dizziness, nasal congestion, and low blood pressure when standing up quickly.

5-alpha reductase inhibitors (5-ARIs), like finasteride and dutasteride, block the enzyme that converts testosterone to DHT. By starving the gland of its primary growth signal, 5-ARIs can reduce prostate volume by about a quarter over a year.¹³ They work best in men with larger prostates and take months to show full benefit. Importantly, stopping a 5-ARI leads to prostate regrowth and worsening symptoms, which is why lifelong use is often recommended for men who respond well.¹³

Many men end up on combination therapy, taking an alpha-blocker and a 5-ARI together to get both quick symptom relief and long-term prostate shrinkage. Another variation pairs a 5-ARI with the erectile-dysfunction drug tadalafil instead of an alpha-blocker. A head-to-head trial found that within three months, tadalafil plus finasteride improved urinary symptoms comparably to tamsulosin plus finasteride, with the added benefit of better sexual function in the tadalafil group.¹⁴

Minimally Invasive Office Procedures

For men who want more relief than pills provide but want to avoid traditional surgery, several in-office or outpatient procedures have emerged in recent years. Two of the most commonly discussed are UroLift and Rezum.

UroLift uses tiny implants to pin back the lobes of the prostate, mechanically opening the urethra without removing tissue. Rezum delivers targeted steam injections into the prostate, killing excess tissue that the body then gradually reabsorbs. A large multicenter analysis comparing the two found that Rezum had lower reintervention rates over five years (about 7% versus 11% for UroLift), suggesting more durable results. However, Rezum also caused more short-term complications, with urinary retention occurring in roughly a quarter of patients in the recovery period.¹⁵

A network meta-analysis comparing these newer procedures to traditional surgery (TURP) and the water-jet technique Aquablation found that the resective approaches, TURP and Aquablation, delivered greater improvements in symptom scores and urine flow. UroLift and Rezum did not differ significantly from each other in urinary outcomes at two years. Where UroLift stood out was in preserving sexual function better than TURP, though not better than Aquablation.¹⁶ The practical message is that minimally invasive procedures trade some urinary improvement for a lighter anesthetic, faster recovery, and better odds of keeping ejaculatory function intact.

Surgery for Larger Prostates

When the prostate is large or symptoms are severe, surgery remains the most effective option. Transurethral resection of the prostate, or TURP, has been the gold standard for decades. The surgeon passes an instrument through the urethra and shaves away obstructing tissue. It works reliably, but it requires general or spinal anesthesia, a hospital stay, and a catheter for several days.

Holmium laser enucleation of the prostate (HoLEP) has been gaining ground. Multiple meta-analyses of randomized trials have consistently found that HoLEP produces results that match or exceed TURP in urinary symptom improvement, particularly at 12 months and beyond, while causing less blood loss, shorter catheter time, shorter hospital stays, and a lower rate of blood transfusion. The trade-offs: HoLEP takes longer in the operating room and carries a higher rate of temporary painful urination (dysuria) afterward.¹⁷ A more recent meta-analysis confirmed these findings and additionally showed that HoLEP carried a lower risk of hyponatremia (a dangerous drop in blood sodium that occasionally occurs with TURP) and urethral stricture.¹⁸

For very large glands, open or robotic simple prostatectomy is sometimes necessary. These are bigger operations with longer recovery, but they remain relevant when the prostate is too large for transurethral techniques.

How Treatment Affects Ejaculation and Erections

Sexual side effects are among the biggest concerns men have when weighing treatment options, and the differences between therapies are substantial. A systematic review and meta-analysis of drug trials found that ejaculatory dysfunction was significantly more common with alpha-blockers than with placebo, but the risk varied enormously by drug. Tamsulosin and silodosin carried the highest risk, while doxazosin and terazosin were no different from placebo. 5-ARIs also increased ejaculatory dysfunction compared to placebo, and combination therapy (an alpha-blocker plus a 5-ARI together) raised the risk further still.¹⁹

Surgical treatments have a more dramatic impact. TURP causes retrograde ejaculation, where semen goes backward into the bladder instead of forward, in roughly half to 70% of patients. HoLEP and similar laser enucleation techniques produce retrograde ejaculation in about 11% to 36% of cases, depending on how much tissue near the ejaculatory ducts is preserved.²⁰ Newer procedures like UroLift, Rezum, and Aquablation were specifically developed with ejaculation preservation in mind, and short-term results are promising, though long-term data are still maturing.

Erectile dysfunction is a separate issue. Surgery causes new-onset ED in about 10% of cases, minimally invasive procedures in 1% to 3%, and drug therapy in 3% to 10%.²¹ For many men, preserving sexual function is a deciding factor in choosing between equally effective treatments, which is a perfectly legitimate basis for that decision.

What Happens If You Leave BPH Untreated

BPH is “benign” in the cancer sense, but that does not mean it is harmless if ignored. Over time, chronic obstruction can lead to acute urinary retention (a sudden inability to urinate at all, which is a medical emergency), chronic urinary retention, recurrent urinary tract infections, bladder stones, damage to the bladder wall, and in severe cases, kidney damage from back-pressure on the urinary system.²² Historically, BPH surgery existed primarily to prevent death from kidney failure. Modern treatment has shifted toward quality-of-life improvement, but the serious complications have not disappeared.²³

The bladder, in particular, can suffer permanent changes. When it has to push against a chronically obstructed urethra for years, the muscular wall thickens and eventually loses its ability to contract effectively. At that point, even successful prostate surgery may not fully restore normal urination because the bladder itself has been structurally damaged. This is one of the stronger arguments for not indefinitely delaying treatment when symptoms are progressing.

Lifestyle Factors and Diet

Modifiable risk factors play a larger role in BPH than many men realize. Physical inactivity, smoking, and heavy alcohol use all correlate with higher rates of BPH medication prescriptions at the population level.²⁴ A review of dietary influences found that moderate exercise and the type and amount of protein in the diet have a meaningful influence on symptom severity.²⁵

More recent research has drawn attention to the gut microbiome and inflammatory dietary patterns. Diets high in red meat and animal protein but low in fiber promote systemic inflammation, which, as discussed earlier in this article, feeds directly into the metabolic pathways linked to prostate growth. Physical inactivity compounds the problem.²⁶ None of this means you can exercise away a prostate that is already enlarged, but staying active and eating a plant-forward, fiber-rich diet may slow progression and reduce symptom burden alongside medical therapy.

What About Saw Palmetto and Other Herbal Remedies

Saw palmetto extract is one of the most popular supplements marketed for prostate health. The evidence, however, is discouraging. A well-designed randomized trial published in the New England Journal of Medicine found no significant difference between saw palmetto and placebo in symptom scores, maximum flow rate, prostate size, residual volume after voiding, quality of life, or PSA levels over one year.²⁷ Some earlier systematic reviews had suggested modest benefits, but controlled trials have not backed them up, and a lack of standardized formulations muddies the waters further.²⁸

Other plant extracts, including Pygeum africanum (African plum tree bark) and Hypoxis rooperi (African star grass), have shown improvements in flow rates and symptoms compared to placebo in systematic reviews, while rye grass pollen (Secale cereale) improved symptoms but not flow rates.²⁹ These are far less studied than the mainstream drug options, and quality control in the supplement market is uneven. If you try herbal remedies, they should not replace proven treatments, especially in men with progressive symptoms.

BPH and Cancer Risk

A common worry among men diagnosed with BPH is whether it increases the chance of developing prostate cancer. The two conditions arise from different parts of the gland and through different biological pathways, so BPH does not “turn into” cancer. That said, a meta-analysis of observational studies found a statistical association between a history of BPH and a higher incidence of both prostate cancer and bladder cancer. In case-control studies, men with BPH had about four times the risk of prostate cancer; in cohort studies, the increase was smaller but still present.³⁰ A Mendelian randomization study using genetic data found evidence of a causal link in both directions: genetic predisposition to BPH increased the risk of prostate cancer, and genetic predisposition to prostate cancer increased the risk of BPH.³¹

The practical implication is not that BPH should cause alarm about cancer. Rather, men already being seen for BPH are undergoing regular exams and PSA monitoring, which creates more opportunities to catch early cancers. The shared risk factors of age, hormones, and inflammation probably explain much of the overlap. What matters is that a BPH diagnosis does not substitute for ongoing cancer screening; the two need separate attention.

Emerging Approaches

Prostate artery embolization (PAE) is a newer option performed by interventional radiologists rather than urologists. A catheter threaded through the groin or wrist delivers tiny particles into the arteries feeding the prostate, cutting off its blood supply. The starved tissue then shrinks through a combination of cell death, fibrosis, and gland contraction. Studies have reported prostate volume reductions of more than 44% after PAE.³² PAE’s appeal is that it avoids general anesthesia and has a low rate of retrograde ejaculation, though it does carry a roughly 10% re-intervention rate within 12 months.²⁰

One creative combination approach pairs PAE with Aquablation, the water-jet surgery. Pre-operative PAE followed by Aquablation significantly reduced post-operative bleeding, lowered rates of urinary retention after the procedure, and made reoperation within 30 days less likely compared to Aquablation alone.³³ Whether this two-stage approach will become mainstream depends on larger trials, but it reflects a broader trend: rather than one-size-fits-all surgery, clinicians are mixing and matching techniques to reduce complications while maintaining strong outcomes.

An Oddity of Comparative Biology

Of all the hundreds of mammalian species that possess a prostate gland, only two are known to develop both benign prostatic hyperplasia and prostate cancer: humans and dogs.³⁴ This makes the dog a valuable model for research, but it also raises an unanswered question: what is it about the human (and canine) prostate that predisposes it to this particular form of overgrowth when most other mammals seem immune? The answer probably lies somewhere in the hormonal milieu and lifespan of these two species, but the specifics remain unclear. For now, it is a reminder that BPH is not just an inevitable consequence of having a prostate. It is a quirk of human biology that researchers are still working to fully explain.