The Flow Pills Formula Explained

Flow Pills is smööts' kidney cleanse and water drainage formula, made for anyone who feels puffy, bloated with fluid, or generally "held onto water" around their cycle, after salty food, or during travel. It combines three traditional diuretic botanicals with potassium citrate, a mineral salt studied for supporting healthy urine composition, and Bioperine to help with absorption. It is a short-term, occasional-use formula for fluid comfort, not a treatment for any diagnosed kidney or urinary condition.

60 vegan capsules per pot, 2 a day = a 30-day supply, best used in short courses rather than continuously. Each capsule combines Uva ursi, Orthosiphon, Dandelion leaf, Potassium citrate and Bioperine (black pepper extract). Because this formula includes Potassium citrate, its potassium content is set against the EU's Nutrient Reference Value (NRV) for potassium, as set out in Annex XIII of Regulation (EU) No 1169/2011.^[1]

Uva ursi in Flow Pills

Uva ursi, or bearberry, is the dried leaf of Arctostaphylos uva-ursi, a low-growing shrub found across the northern hemisphere. Its leaves are rich in arbutin, a compound that the body converts into hydroquinone derivatives, which are then concentrated in the urine. Traditionally it has been used as a short-term urinary tonic, and it is included here for that traditional, urine-concentrated use rather than as a general hormone or fluid regulator.

Human research has focused on uncomplicated urinary tract infection rather than general "water retention". In the REGATTA trial, a double-blind, randomised, controlled comparative-effectiveness study in German general practice, women with uncomplicated UTI symptoms treated initially with uva ursi used fewer antibiotic courses than expected, though symptom relief was slower than with antibiotics in some participants.^[2] A related analysis from the same research group compared uva ursi extract directly with the antibiotic fosfomycin in primary care.^[3] A separate factorial randomised trial (ATAFUTI) testing uva ursi against placebo for symptom relief in UTI found no significant difference between groups, a useful reminder that not every trial of this herb has been positive.^[4] Pharmacokinetic work in healthy volunteers has confirmed that arbutin is absorbed and excreted into urine as active hydroquinone conjugates within hours of an oral dose, which is the basis for how it is thought to act locally in the urinary tract.^[5]

To be clear about the limits: the strongest human trials looked at infection symptoms, not fluid retention or "detox" claims, and results were mixed even there. Regulatory risk assessments have looked closely at the hydroquinone content of uva ursi and concluded it is intended for short, occasional courses rather than continuous daily use, which is reflected in the cautions below.^[6]

Orthosiphon in Flow Pills

Orthosiphon, also called Java tea or cat's whiskers (Orthosiphon stamineus, sometimes named Orthosiphon aristatus), is a leaf traditionally brewed across Southeast Asia as a diuretic tea and general kidney tonic. Its leaves contain flavonoids and terpenoids that have been studied for effects on urine output and uric acid handling.

Most of the pharmacological evidence for Orthosiphon's diuretic action comes from animal research: a controlled study in rats found a dose-dependent increase in urine output with Orthosiphon extract, alongside increased potassium excretion, though the effect was less pronounced than with conventional diuretic drugs used for comparison.^[7] Human evidence is thinner. A randomised controlled trial in people with recurrent kidney stones and multiple chronic urinary complaints compared Orthosiphon capsules with placebo over two weeks; both groups improved, but Orthosiphon did not outperform placebo on the measured symptom scores.^[8] Laboratory work has also examined how Orthosiphon extract interacts with human liver enzymes involved in drug metabolism, which is relevant background for anyone taking regular medication.^[9] A comprehensive review of the plant's traditional use, chemistry and pharmacology summarises this wider evidence base, noting consistent diuretic and mild uric-acid-lowering effects in preclinical models.^[10]

We are including Orthosiphon on the strength of long traditional use and consistent animal pharmacology, but we want to be straightforward that the one placebo-controlled human trial available did not show a clear added benefit over placebo for urinary symptoms. This is a live gap in the evidence, and larger, better-designed human trials are needed before stronger claims could be justified.

Dandelion leaf in Flow Pills

Dandelion leaf comes from Taraxacum officinale, the common flowering plant, and has one of the longest folk histories as a diuretic of any European herb (its old French nickname, "pissenlit", literally means this).^[11] It is rich in potassium and flavonoids, which may help explain why traditional use paired it with a mineral that is usually lost during diuresis with pharmaceutical water pills.

The clearest human evidence is a small pilot study in 17 healthy volunteers given a fresh-leaf hydroethanolic dandelion extract three times over a single day. Compared with their own two-day baseline, urinary frequency and the fluid excretion ratio rose significantly within hours of the first dose, with no adverse events reported.^[12] A 2025 review pulling together the wider phytochemical and pharmacological literature on Taraxacum species describes consistent diuretic, anti-inflammatory and antioxidant activity linked to its polyphenol and flavonoid content, largely from laboratory and animal work.^[13] A separate laboratory study isolating dandelion's anti-inflammatory activity found it reduced inflammatory markers in cell and animal models, supporting a plausible mechanism for the mild anti-inflammatory effect it is traditionally credited with in the urinary tract.^[14]

The honest picture: the single-day human pilot study is small, unblinded and uncontrolled by a placebo arm, so while it is a genuinely useful first human data point, it does not prove a lasting effect over weeks of use. Most of the rest of the evidence for dandelion leaf is preclinical. It remains one of the better-studied traditional diuretics we could have chosen, but the human evidence base is still thin.

Potassium citrate in Flow Pills

Potassium citrate is a mineral salt combining potassium with citric acid. Unlike the three botanicals above, it is not a herbal extract, and its research base sits mostly in urology rather than traditional medicine: it has been studied for decades for its effect on urine composition, particularly urinary citrate and pH, both of which influence how comfortably the urinary system handles fluid and mineral load.^[15][16]

The best evidence comes from trials in people prone to calcium kidney stones, a population in which potassium citrate's effect on urine chemistry has been measured most rigorously. A randomised, double-blind trial in patients with low urinary citrate and recurrent calcium stones found that three years of potassium citrate normalised urinary citrate and dramatically reduced new stone formation compared with placebo.^[17] A separate randomised trial using potassium-magnesium citrate over three years found new stones formed in under 13% of the treatment group compared with over 63% of the placebo group.^[18] A more recent randomised study found potassium citrate reduced urinary calcium excretion as effectively as the diuretic hydrochlorothiazide in people with high urinary calcium.^[19] Long-term follow-up data spanning up to several years confirm potassium citrate produces a sustained rise in urinary pH and citrate with continued use.^[20] A 2015 Cochrane systematic review of citrate salts for calcium kidney stones concluded that citrate therapy reduces new stone formation and stabilises existing stone size, based on pooled data from several of these trials.^[21]

These trials were mostly run in people with a stone-forming history, not in the general population using it for everyday fluid comfort, so the citrate and urine-composition benefits are better established than any general "feeling less bloated" effect, which has not been directly measured in trials.

Bioperine in Flow Pills

Bioperine is a patented, standardised extract of black pepper (Piper nigrum) fruit, standardised to a set level of piperine, its main active alkaloid. As in our other formulas, it is included here to support the absorption of the other ingredients rather than for a fluid-balance effect of its own.

Piperine's absorption-enhancing action was first characterised in pharmacokinetic studies showing rapid intestinal uptake and inhibition of enzymes and transporters that would otherwise limit how much of a compound reaches the bloodstream.^[22] In a human and animal study, a 20 mg dose of piperine taken alongside curcumin increased peak blood levels of curcumin roughly twentyfold in human volunteers.^[23] A separate double-blind, placebo-controlled study in healthy men found that 21 days of piperine alongside coenzyme Q10 produced around 30% greater plasma CoQ10 levels than CoQ10 taken alone.^[24]

These trials used curcumin and coenzyme Q10 as the test compounds, not the specific botanicals or potassium citrate in Flow Pills, so its benefit here is a reasonable, mechanism-based inference rather than something measured directly in this exact combination. Because piperine can also affect how the body processes certain medications, it is worth flagging to a doctor or pharmacist if you take regular prescription drugs.

How to take

Take 2 capsules a day with a full glass of water. Flow Pills is designed for short, occasional courses (for example, the days around your cycle, after a salty weekend, or while travelling) rather than continuous year-round use. Do not use uva ursi-containing products for more than one to two weeks at a time, and take a break of several weeks between courses.

Ingredients and nutritional information

Each pack contains: 60 capsules · 30 days

Serving: 2 capsules daily, with a large glass of water.

Active ingredients: Uva ursi leaf extract, Orthosiphon (Java tea) leaf extract, Dandelion leaf extract, Potassium citrate, Bioperine (black pepper extract).

*NRV: Nutrient Reference Value, Regulation (EU) No 1169/2011. † No NRV established.

Cautions and allergen advice

• Pregnancy and breastfeeding: Do not use Flow Pills during pregnancy or breastfeeding. Uva ursi, Orthosiphon and dandelion leaf have not been adequately studied in pregnancy, and diuretic-type herbs are generally avoided due to their effect on fluid and mineral balance.
• Medications: Potassium citrate should not be combined with potassium-sparing diuretics, ACE inhibitors, angiotensin receptor blockers or other potassium supplements without medical supervision, because of the risk of raised blood potassium. Uva ursi should not be combined with vitamin C or other urine-acidifying supplements, as an acidic urine reduces its intended activity. Bioperine can increase the absorption of some prescription medications; check with a pharmacist if you take regular medicine.
• Duration of use: Uva ursi is intended for short-term use only, no more than one to two weeks at a time, and no more than a few short courses a year, due to its hydroquinone content.
• Children: Not intended for anyone under 18.
• Medical conditions: Avoid if you have kidney disease, are on dialysis, or have any condition affecting potassium handling (such as Addison's disease or adrenal insufficiency), due to the potassium citrate content. Avoid dandelion if you have bile duct obstruction, gallstones, or a known allergy to plants in the daisy (Asteraceae/Compositae) family, such as ragweed, marigold or chrysanthemum. Speak to your doctor before use if you have existing kidney, heart or liver disease causing fluid retention, as this needs proper medical management rather than a supplement.
• Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose.

Allergen advice

Flow Pills is formulated without any of the 14 EU-listed allergens as intentional ingredients: Uva ursi, Orthosiphon, Dandelion leaf, Potassium citrate and Bioperine are all plant or mineral-derived, and the capsule shell is vegan. Anyone with a known plant allergy, including to the daisy (Asteraceae/Compositae) family that dandelion belongs to, should check the individual ingredients against their own sensitivities, as noted in the medical conditions caution above.

Flow Pills is produced in a facility that also handles other food supplement ingredients and follows standard allergen control procedures to minimise the risk of cross-contact. Always read the label before use, particularly if you have a diagnosed food allergy or intolerance.

References

1. European Parliament and Council of the European Union. (2011). Regulation (EU) No 1169/2011 on the provision of food information to consumers, Annex XIII: Reference intakes. Official Journal of the European Union. eur-lex.europa.eu
2. Afshar K, Fleischmann N, Schmiemann G, Bleidorn J, Hummers-Pradier E, Friede T, Wegscheider K, Moore M, Gágyor I. Reducing antibiotic use for uncomplicated urinary tract infection in general practice by treatment with uva-ursi (REGATTA) - a double-blind, randomized, controlled comparative effectiveness trial. BMC Complement Altern Med. 2018 Jul 3;18(1):203. doi:10.1186/s12906-018-2266-x
3. Gágyor I, Hummers E, Schmiemann G, Friede T, Pfeiffer S, Afshar K, Bleidorn J. Herbal treatment with uva ursi extract versus fosfomycin in women with uncomplicated urinary tract infection in primary care: a randomized controlled trial. Clin Microbiol Infect. 2021 Oct;27(10):1441-1447. doi:10.1016/j.cmi.2021.05.032
4. Moore M, Trill J, Simpson C, et al. Uva-ursi extract and ibuprofen as alternative treatments for uncomplicated urinary tract infection in women (ATAFUTI): a factorial randomized trial. Clin Microbiol Infect. 2019 Aug;25(8):973-980. doi:10.1016/j.cmi.2019.01.011
5. Schindler G, Patzak U, Brinkhaus B, von Niecieck A, Wittig J, Krähmer N, Glöckl I, Veit M. Urinary excretion and metabolism of arbutin after oral administration of Arctostaphylos uvae ursi extract as film-coated tablets and aqueous solution in healthy humans. J Clin Pharmacol. 2002 Aug;42(8):920-7. doi:10.1177/009127002401102740
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8. Premgamone A, Sriboonlue P, Maskasem S, Ditsataporncharoen W, Jindawong B. Orthosiphon versus placebo in nephrolithiasis with multiple chronic complaints: a randomized control trial. Evid Based Complement Alternat Med. 2009 Dec;6(4):495-501. doi:10.1093/ecam/nem141
9. Pan Y, Abd-Rashid BA, Ismail Z, Ismail R, Mak JW, Pook PC, Er HM, Ong CE. In vitro effects of active constituents and extracts of Orthosiphon stamineus on the activities of three major human cDNA-expressed cytochrome P450 enzymes. Chem Biol Interact. 2011 Mar 15;190(1):1-8. doi:10.1016/j.cbi.2011.01.022
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11. National Center for Complementary and Integrative Health. (n.d.). Dandelion. National Institutes of Health. nccih.nih.gov
12. Clare BA, Conroy RS, Spelman K. The diuretic effect in human subjects of an extract of Taraxacum officinale folium over a single day. J Altern Complement Med. 2009 Aug;15(8):929-34. doi:10.1089/acm.2008.0152
13. Tanasa Acretei MV, Negreanu-Pirjol T, Olariu L, Negreanu-Pirjol BS, Lepadatu AC, Anghel Cireasa L, Rosoiu N. Bioactive Compounds from Vegetal Organs of Taraxacum Species (Dandelion) with Biomedical Applications: A Review. Int J Mol Sci. 2025 Jan 7;26(2). doi:10.3390/ijms26020450
14. Jeon HJ, Kang HJ, Jung HJ, Kang YS, Lim CJ, Kim YM, Park EH. Anti-inflammatory activity of Taraxacum officinale. J Ethnopharmacol. 2008 Jan 4;115(1):82-8. doi:10.1016/j.jep.2007.09.006
15. Office of Dietary Supplements. (n.d.). Potassium: Fact sheet for health professionals. National Institutes of Health. ods.od.nih.gov
16. Linus Pauling Institute. (n.d.). Potassium. Micronutrient Information Center, Oregon State University. lpi.oregonstate.edu
17. Barcelo P, Wuhl O, Servitge E, Rousaud A, Pak CY. Randomized double-blind study of potassium citrate in idiopathic hypocitraturic calcium nephrolithiasis. J Urol. 1993 Dec;150(6):1761-4. doi:10.1016/s0022-5347(17)35888-3
18. Ettinger B, Pak CY, Citron JT, Thomas C, Adams-Huet B, Vangessel A. Potassium-magnesium citrate is an effective prophylaxis against recurrent calcium oxalate nephrolithiasis. J Urol. 1997 Dec;158(6):2069-73. doi:10.1016/s0022-5347(01)68155-2
19. Solak V, Gökce Mİ, Yaman Ö. Potassium citrate vs. hydrochlorothiazide to reduce urinary calcium excretion in calcium oxalate stone patients with hypercalciuria: a prospective randomized study. Int Urol Nephrol. 2021 Sep;53(9):1791-1796. doi:10.1007/s11255-021-02879-7
20. Pak CY, Fuller C, Sakhaee K, Preminger GM, Britton F. Long-term treatment of calcium nephrolithiasis with potassium citrate. J Urol. 1985 Jul;134(1):11-9. doi:10.1016/s0022-5347(17)46962-x
21. Phillips R, Hanchanale VS, Myatt A, Somani B, Nabi G, Biyani CS. Citrate salts for preventing and treating calcium containing kidney stones in adults. Cochrane Database Syst Rev. 2015 Oct 6;2015(10):CD010057. doi:10.1002/14651858.CD010057.pub2
22. Khajuria A, Zutshi U, Bedi KL. Permeability characteristics of piperine on oral absorption--an active alkaloid from peppers and a bioavailability enhancer. Indian J Exp Biol. 1998 Jan;36(1):46-50. PubMed
23. Shoba G, Joy D, Joseph T, Majeed M, Rajendran R, Srinivas PS. Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers. Planta Med. 1998 May;64(4):353-6. doi:10.1055/s-2006-957450
24. Badmaev V, Majeed M, Prakash L. Piperine derived from black pepper increases the plasma levels of coenzyme Q10 following oral supplementation. J Nutr Biochem. 2000 Feb;11(2):109-13. doi:10.1016/s0955-2863(99)00074-1