Home Ingredients Plasys300® (Rye Pollen and Beta-Sitosterol Blend, Pharmactive)
Prostate HealthKidney/Urinary Tract

Plasys300® (Rye Pollen and Beta-Sitosterol Blend, Pharmactive)

Evidence Level
Limited
3 Clinical Trials
7 Documented Benefits
2/5 Evidence Score

Plasys300 is an ingredient from Pharmactive Biotech Products (Spain) that combines cereal pollen (chiefly rye pollen) with plant sterols, mainly beta-sitosterol, sold for men's prostate and urinary comfort. The manufacturer states it is standardized to at least 50% phytosterols and at least 1% essential amino acids; some trade coverage reports the amino acid figure as below 1%. Plasys300 itself has never been tested against a placebo. Its only human data is an uncontrolled 8-week company consumer survey of 50 men with frequent nighttime urination, reported in a press release. The controlled evidence for this type of ingredient comes from other products: a different rye pollen extract (Cernilton), a four-ingredient combination that also contained saw palmetto, and other beta-sitosterol preparations tested in men with benign prostatic enlargement. See a doctor before self-treating urinary symptoms.

Studied Dose 300 mg/day orally in an uncontrolled 8-week company consumer survey; no controlled trial of Plasys300 exists.
Active Compound Cereal pollen (predominantly rye pollen) plus beta-sitosterol. Manufacturer specification: at least 50% phytosterols (as beta-sitosterol, by GC) and at least 1% essential amino acids (by HPLC).

Benefits

Nighttime urination: self-reported in an uncontrolled survey

In an 8-week company consumer survey, 50 men aged 40 to 60 with frequent nighttime urination took 300 mg a day and rated themselves online; 90% said they woke fewer times to urinate. There was no placebo group, no bladder diary and no peer-reviewed publication. Nighttime urination improves substantially on placebo in controlled trials, so this figure cannot show that Plasys300 caused the change. Controlled evidence for fewer nighttime trips comes from a different rye pollen extract (Cernilton) in men with prostate enlargement, where the benefit was modest.

Supported by Trial 1

Urinary urgency: self-reported, no control group

In the same uncontrolled consumer survey, 88% of the 50 men said their urgency (the sudden, hard-to-defer need to urinate) was reduced. No placebo arm was included and no validated urgency score was reported. The controlled studies cited on this page do not report urgency as a separate result in their published summaries: the Cernilton review reported overall self-rated symptoms and nocturia, and the combination trial reported nocturia, daytime frequency and total symptom score.

Supported by Trial 1, Trial 2

Sleep and well-being: self-reported only

More than 80% of the 50 survey participants said their sleep and overall well-being improved. These were online self-ratings without a control group, so they cannot separate an effect of the capsule from placebo response, expectation or natural variation. Sleep and quality of life have not been measured in a controlled trial of Plasys300.

Supported by Trial 1

Beta-sitosterol: modest short-term evidence from other products

A 1999 systematic review (Wilt, BJU International) pooled 4 double-blind placebo-controlled trials in 519 men with benign prostatic enlargement lasting 4 to 26 weeks. Beta-sitosterol preparations (60 mg/day and 130 mg/day in the two largest trials) improved symptom scores by about 4.9 IPSS points and peak urine flow by about 3.9 mL/s but did not shrink the prostate, and the authors noted short trials and unstandardized preparations. A 2023 review judged the benefit generally smaller than that of prescription drugs. None of these trials tested Plasys300.

Supported by Trial 3

Laboratory cell studies (not tested in people)

Pharmactive reports an unpublished laboratory study in which the phytosterol fraction of Plasys300 slowed the growth of prostate cells in a dish and inhibited 5-alpha-reductase, the enzyme that converts testosterone to dihydrotestosterone (DHT). The company provides references only on request. Cell culture results do not show that the capsule affects the prostate in a living person, and nothing here shows any effect on prostate cancer.

Supported by Trial 2

Hormone effects: not measured in people

The manufacturer states that beta-sitosterol inhibits testosterone production, but no human study of Plasys300, and none of the beta-sitosterol trials summarized on this page, measured testosterone or DHT. The company's laboratory claim concerns 5-alpha-reductase, the enzyme that converts testosterone to DHT, which is not the same as lowering testosterone production. In controlled trials, beta-sitosterol did not reduce prostate size.

Supported by Trial 2, Trial 3

Rye pollen: controlled evidence is for a different extract

No human study has shown an anti-inflammatory effect of Plasys300, and the stated 1% essential amino acid specification corresponds to roughly 3 mg per 300 mg capsule. The controlled human pollen evidence is for Cernilton, a different rye grass pollen extract, which modestly improved self-rated symptoms and nighttime urination in short trials in men with prostate enlargement but did not improve urine flow, residual urine or prostate size.

Supported by Trial 3, Trial 1

Mechanism of action

1

5α-reductase inhibition

5-alpha-reductase converts testosterone to dihydrotestosterone (DHT), the androgen most involved in prostate growth. Pharmactive reports that the phytosterol fraction of Plasys300 inhibited this enzyme in an unpublished laboratory study. Whether a 300 mg capsule lowers DHT in a living person has not been measured, and beta-sitosterol trials in men did not reduce prostate size.

2

Prostate cell growth in the laboratory

An unpublished company laboratory study reports that the phytosterol fraction of Plasys300 slowed the growth of prostate cell lines in culture. Cells grown in a dish do not show what happens in human prostate tissue after swallowing a capsule, and no effect on prostate size or on prostate cancer has been shown in people.

3

Rye pollen and inflammation (not shown in people)

Inflammation in the prostate is associated with urinary symptoms in older men. The manufacturer describes the essential amino acids in pollen as anti-inflammatory, but the stated amino acid content is roughly 3 mg per capsule, and no anti-inflammatory effect of Plasys300 has been measured in people or reported in a published study.

4

Smooth muscle effects (not studied)

Urinary symptoms in older men can come from enlarged prostate tissue and from tension in prostate and bladder smooth muscle. No published study has tested whether Plasys300 relaxes urinary tract smooth muscle, and neither Cernilton nor beta-sitosterol reduced prostate size in controlled trials.

5

Antioxidant activity (not studied)

No antioxidant testing of Plasys300 has been published, and antioxidant activity in a test tube has not been shown to protect prostate tissue or change urinary symptoms in people.

Clinical trials

1
Uncontrolled Company Consumer Survey (No Placebo, Unpublished): Plasys300 and Nighttime Urination

Company-run 8-week consumer survey of Plasys300 at 300 mg/day in men aged 40 to 60 with frequent nighttime urination, announced in an October 2024 press release. Every participant took the product; there was no placebo or comparison group, and outcomes were online self-assessments of urgency, nighttime urination, sleep and well-being. No validated questionnaire is named and no peer-reviewed report exists.

50 healthy male participants aged 40-60 with frequent nocturia. 8-week intervention.

According to the company, 88% reported less urgency, 90% reported fewer nighttime awakenings and more than 80% reported better sleep and well-being; close to 90% also said they intended to buy the product and would recommend it. Without a placebo group these percentages cannot show an effect of Plasys300, because nighttime urination and urgency improve markedly on placebo in controlled trials.

2
Laboratory Cell Studies Only (Not a Human Trial, Unpublished)

In vitro studies on prostate cell lines characterizing Plasys300's mechanism of action. Tested antiproliferative effects, 5-alpha-reductase inhibition, and impact on related prostate biology pathways. The results have not been published; the company provides references only on request.

Not applicable — in vitro cell culture studies on prostate cell lines.

Plasys300's phytosterol fraction demonstrated antiproliferative effects on prostate cell lines and capacity to inhibit 5-alpha-reductase. These are cell culture results. They do not show that Plasys300 affects the prostate, urinary symptoms or hormone levels in people, and they do not explain the uncontrolled survey results.

3
Borrowed Evidence: Review of Other Beta-Sitosterol Products in Men With Prostate Enlargement (Wilt 1999)
PubMed

Systematic review by Wilt, MacDonald and Ishani (BJU International, 1999) of randomized double-blind placebo-controlled trials of beta-sitosterol preparations (Harzol, Azuprostat and WA184), none of them Plasys300. Outcomes were symptom scores (IPSS), peak urine flow, residual urine volume and prostate size.

519 men with symptomatic benign prostatic enlargement in 4 double-blind trials lasting 4 to 26 weeks; the two largest used 60 mg/day and 130 mg/day of beta-sitosterol.

Compared with placebo, beta-sitosterol improved IPSS by 4.9 points (2 trials), peak urine flow by 3.91 mL/s and residual volume by 28.6 mL (4 trials), but did not reduce prostate size, and the trial of pure beta-sitosteryl glucoside (WA184) showed no flow improvement. The authors noted short treatment, unstandardized preparations and unknown long-term effectiveness and safety. These results apply to other beta-sitosterol products, not to Plasys300.

Side effects and drug interactions

Common Potential side effects

See a doctor before self-treating urinary symptoms. Frequent nighttime urination, urgency or a weak stream can be caused by prostate enlargement, prostate cancer, infection, diabetes, heart failure, sleep apnea or medicines, and a supplement can delay a needed diagnosis.
Side effects in controlled trials of beta-sitosterol and of Cernilton were uncommon and mild; withdrawal rates on beta-sitosterol were similar to placebo (7.8% vs 8.0%).
Pollen allergy: rye pollen is a grass pollen. Avoid this product if you are allergic to grass pollen.
Do not use if you have sitosterolemia (phytosterolemia), a rare inherited disorder in which plant sterols such as beta-sitosterol build up in the blood and are linked to early heart disease.
Long-term safety is not established: the beta-sitosterol and Cernilton trials lasted at most 26 weeks, and Plasys300 itself has only an 8-week uncontrolled survey.
Sold for men; it has not been studied in women, in pregnancy or during breastfeeding.
The company reports the 8-week consumer survey (50 men, 300 mg/day) as well tolerated, but no safety data from a controlled trial of Plasys300 has been published.

Important Drug interactions

Finasteride or dutasteride: combined use has not been studied. Tell your prescriber, and do not use a supplement in place of a prescribed prostate medicine.
Alpha-blockers (tamsulosin, alfuzosin): no interaction has been studied. Tell your prescriber if you take one.
Cholesterol-lowering medicines: plant sterols lower LDL cholesterol at 1.5 to 3 g/day; the roughly 150 mg of phytosterols in one capsule is far below that, so a meaningful added effect is unlikely.
Testosterone therapy: no effect of Plasys300 on testosterone has been measured in people. Tell your prescriber if you use it.
Anticoagulants: no interaction has been documented. Tell your prescriber if you take warfarin or another blood thinner.
Men with new or worsening urinary symptoms should be examined by a doctor before using this product.

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Frequently asked questions about Plasys300® (Rye Pollen and Beta-Sitosterol Blend, Pharmactive)

What is Plasys300?

Plasys300 is an ingredient from Pharmactive Biotech Products (Spain) that combines cereal pollen (chiefly rye pollen) with plant sterols, mainly beta-sitosterol, sold for men's prostate and urinary comfort.

What is Plasys300 used for?

Plasys300 is researched primarily for Prostate Health and Kidney/Urinary Tract. In an 8-week company consumer survey, 50 men aged 40 to 60 with frequent nighttime urination took 300 mg a day and rated themselves online; 90% said they woke fewer times to urinate.

What is the recommended dosage of Plasys300?

The clinically studied dose is 300 mg/day orally in an uncontrolled 8-week company consumer survey; no controlled trial of Plasys300 exists. Always follow the product label and check with a healthcare provider for personal advice.

Is Plasys300 safe, and does it have side effects?

For most healthy adults, Plasys300 is well tolerated at studied doses. Reported effects can include: See a doctor before self-treating urinary symptoms. Frequent nighttime urination, urgency or a weak stream can be caused by prostate enlargement, prostate cancer, infection, diabetes, heart failure, sleep apnea or medicines, and a supplement can delay a needed diagnosis. It may also interact with some medications. Plasys300 is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Plasys300 interact with any medications?

Possible interactions include: Finasteride or dutasteride: combined use has not been studied. Tell your prescriber, and do not use a supplement in place of a prescribed prostate medicine. Alpha-blockers (tamsulosin, alfuzosin): no interaction has been studied. Tell your prescriber if you take one. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Plasys300?

NutraSmarts rates the evidence for Plasys300 as Limited (2 out of 5). It is backed by 3 clinical trials and 4 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(4 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. MacDonald R, Ishani A, Rutks I, Wilt TJ A systematic review of Cernilton for the treatment of benign prostatic hyperplasia BJU International. 2000;85(7):836-41. doi: 10.1046/j.1464-410x.2000.00365.x.PubMedUsed to support: Systematic review of Cernilton, a rye grass pollen extract that is a different product from Plasys300: 4 controlled trials (2 placebo-controlled, 2 against other products) in 444 men with benign prostatic enlargement, lasting 12 to 24 weeks. Cernilton modestly improved self-rated urinary symptoms (RR 2.40 vs placebo) and nocturia (RR 2.05 vs placebo) but did not improve urine flow, residual volume or prostate size. Allocation concealment was unclear in all trials, and the authors called the evidence limited by short duration, small numbers and unknown preparation quality.
  2. Preuss HG, Marcusen C, Regan J, Klimberg IW, Welebir TA, Jones WA Randomized trial of a combination of natural products (cernitin, saw palmetto, B-sitosterol, vitamin E) on symptoms of benign prostatic hyperplasia (BPH) International Urology and Nephrology. 2001;33(2):217-25. doi: 10.1023/a:1015227604041.PubMedUsed to support: Double-blind placebo-controlled trial in men with benign prostatic enlargement (144 randomized, 127 completed, 3 months) of a four-ingredient combination: cernitin pollen extract, saw palmetto, beta-sitosterol and vitamin E. The combination reduced nocturia (p<0.001), daytime frequency (p<0.04) and total AUA symptom score versus placebo, but did not change urine flow, residual volume or PSA. Plasys300 contains no saw palmetto or vitamin E, so the result cannot be attributed to Plasys300's ingredients alone.
  3. Macoska JA The use of beta-sitosterol for the treatment of prostate cancer and benign prostatic hyperplasia American Journal of Clinical and Experimental Urology. 2023;11(6):467-480.PubMedUsed to support: Narrative review of saw palmetto extract and beta-sitosterol. Its prostate cancer findings come from cell and rodent studies, not people. For men with benign prostatic enlargement, it concludes that beta-sitosterol improves lower urinary tract symptoms, but generally less than prescription alpha-blockers or 5-alpha-reductase inhibitors, and may suit younger men with mild symptoms. It does not study Plasys300.
  4. Wilt TJ, MacDonald R, Ishani A beta-sitosterol for the treatment of benign prostatic hyperplasia: a systematic review BJU International. 1999;83(9):976-83. doi: 10.1046/j.1464-410x.1999.00026.x.PubMedUsed to support: Systematic review of 4 double-blind placebo-controlled trials (519 men with benign prostatic enlargement, 4 to 26 weeks) of beta-sitosterol preparations other than Plasys300. Beta-sitosterol improved IPSS by 4.9 points (2 trials), peak urine flow by 3.91 mL/s and residual volume by 28.62 mL (4 trials), but did not reduce prostate size, and the pure beta-sitosteryl glucoside trial showed no flow improvement. The authors noted short durations, unstandardized preparations and unknown long-term effectiveness and safety.