Pinc PeptideThe girly peptide research blog

VIP (vasoactive intestinal peptide) · Dose evidence · updated 8 October 2026

VIP peptide dosage: what studies actually used

The short answer

VIP (vasoactive intestinal peptide), called aviptadil as a drug, has no FDA-approved product, so there is no US label dose6. The only label dose we found is for Invicorp, a prescription injection into the penis for erectile dysfunction approved in Sweden: 25 µg of aviptadil with 2 mg of phentolamine, no more than once a day or 3 times a week7. In COVID-19, 12-hour IV drips did not improve recovery in the largest trial, of 471 people8. Inhaled aviptadil at 100 µg three times a day was dropped for futility from a US trial after 118 patients, while an 80-person placebo-controlled trial of 200 µg a day reported faster discharge from hospital29. The nasal spray sold for mold illness rests on small studies with no placebo group, the main one using 50 µg four times a day in 20 people1011.

Not dosing advice. This page reports doses that studies and approved labels used, with their sources. It does not recommend a dose, and we do not give mixing, injection or unit-conversion instructions. Gray-market vials often do not contain what their label says. How we report doses.

Every dose studied in people

StudyWhoPeopleDose and routeWhat happened
TESICO (Brown 2023), randomized placebo-controlled trial at 28 US sites Adults in hospital with COVID-19 and acute hypoxemic respiratory failure (low blood oxygen); 94% were in intensive care 471 A 12-hour infusion each day, targeting 600, 1,200 and 1,800 pmol/kg on days 1, 2 and 3
Drip into a vein (IV), in hospital · 3 days		 Recovery at day 90 did not differ (odds ratio 1.11, p = 0.54), and 38% versus 36% had died by day 908. The trial was stopped early for futility, and a day-5 measure combining death, organ failure, serious infections and other serious events was 63% versus 56% (p = 0.10)8.
Al-Mitwalli 2025, retrospective review at one center, with no comparison group Men with erectile dysfunction whose alprostadil injections had caused intolerable pain or failed at the maximum dose of 40 µg 308 Invicorp (aviptadil with phentolamine); the abstract does not give the strength
Injection into the penis · Average follow-up 13.3 months		 182 men (59%) found it effective at 3 months, judged by a return to penetrative sex: 76% of those who had pain with alprostadil and 36% of those for whom it had failed12. Facial flushing affected 69 men (22.5%), and one (0.3%) had ischemic priapism, a prolonged, painful erection12.
Dinsmore 1999, double-blind placebo-controlled study at eight clinics Men with erectile dysfunction of mainly physical cause 236 25 µg VIP with 1 mg or 2 mg phentolamine per injection
Injection into the penis, by a prefilled auto-injector · Up to 12 injections over 6 months in the placebo-controlled phase		 Of 171 men in the placebo-controlled phase, 75% responded to the 1 mg mix versus 12% to placebo, and 66% to the 2 mg mix versus 18% (P < 0.001 for both)13. Flushing followed 40% of 1,711 injections, and there was one priapism (0.06%)13.
COVID-AIV (Youssef 2022), double-blind placebo-controlled trial at 10 US hospitals Adults with critical COVID-19 and respiratory failure, randomized 2 to 1 to aviptadil or placebo 196 50, 100 and 150 pmol/kg per hour, one level each day
Drip into a vein (IV), in hospital · Three 12-hour infusions on 3 days in a row		 The main goal, being alive and free of respiratory failure at day 60, was not met (odds ratio 1.6, 95% CI 0.86 to 3.11)14. Survival at day 60, a key secondary goal that had been the original main one, favored aviptadil (odds ratio 2.0, p = 0.035), and diarrhea affected 32.8% versus 1.5%14.
VP 007, open-label randomized crossover study against alprostadil, as described in a 2017 Welsh assessment Men over 18 with erectile dysfunction for at least a year, in a stable relationship 187 12.5 or 25 µg aviptadil with 0.5, 1.0 or 2.0 mg phentolamine, set for each man in a dose-finding phase
Injection into the penis · A dose-finding phase, then four doses of each product		 In the dose-finding phase, fewer men reached a grade 3 erection, the study’s success measure, with aviptadil and phentolamine than with alprostadil (73% versus 83%)15. In the second phase, open only to men who responded to both, 84% of ampoule injections and 83% of alprostadil injections succeeded, and the assessment called equivalence unclear15.
NCT04360096, randomized placebo-controlled Phase 2/3 trial, stopped by its sponsor People with severe COVID-19 who were receiving oxygen but did not yet have respiratory failure, at 13 US sites 144 100 µg three times a day, or a salt-water placebo
Inhaled by mesh nebulizer · Not stated in the registry record		 The sponsor stopped the trial, giving ‘Sponsor decision’ as the reason, and no results had been posted as of 7 October 20263.
I-SPY COVID, aviptadil arm of an open-label adaptive platform trial, as reported by the trial’s sponsor Critically ill patients in hospital with COVID-19, most on high-flow oxygen through the nose and the rest on ventilators; 51 given aviptadil and 67 concurrent controls, all with dexamethasone and remdesivir 118 100 µg three times a day
Inhaled by nebulizer · Up to 14 days		 The arm was stopped after 118 patients because it met the trial’s futility rule, and the hazard ratio for recovery, 0.56 (95% CI 0.34 to 0.89), favored the controls2. The release, issued with the drug’s maker, suggested that the nebulized drug may not reach the air sacs well in patients on high-flow oxygen or ventilators2.
NCT04536350, randomized double-blind placebo-controlled Phase 2 trial in Switzerland, stopped early Adults in hospital with COVID-19 at risk of acute respiratory distress syndrome (ARDS), a severe form of lung failure, at two Swiss hospitals 83 67 µg three times a day, or a salt-water placebo
Inhaled by nebulizer · 10 days		 It was stopped because few patients in hospital with COVID-19 met the entry criteria, and no results had been posted as of 7 October 20264.
Esendagli 2025, double-blind placebo-controlled Phase 2 trial at 9 hospitals in Turkey Adults in hospital with COVID-19 pneumonia who needed oxygen but not intensive care; 39 given aviptadil, 41 placebo 80 200 µg a day, as two 100 µg doses 30 minutes apart
Inhaled by mesh nebulizer · 7 to 14 days		 Average time to discharge was 7.8 versus 10 days (p = 0.049), and deaths by day 180 were 5.1% versus 12.2%, a difference that was not significant (p = 0.433)9. No one dropped out because of side effects, and a drug company, Centurion Pharma, funded the trial9.
Roy 1990, double-blind placebo-controlled trial of VIP alone Men with erectile dysfunction from diabetes, nerve damage or psychological causes 24 200 or 400 pmol of VIP, or placebo, per injection
Injection into the penis · 3 weekly visits		 Penile length and width increased with dose, but no man reached rigidity adequate for intercourse16.
Shoemaker 2013, open-label study with no placebo group Adults with chronic inflammatory response syndrome (CIRS) linked to water-damaged buildings, not resolved by earlier treatment 20 50 µg four times a day; after six months, patients changed how often they used it
Nasal spray · At least 18 months		 The authors reported that symptoms fell to the level of healthy controls in all treated patients, with no dropouts for side effects; one patient had a temporary rise in lipase, a pancreas enzyme10. With no placebo group, the study cannot show that VIP caused the change.
Leuchte 2008, single-dose study without a control group People with pulmonary hypertension (high blood pressure in the lungs), during heart catheterization 20 One 100 µg dose
Inhaled · Single dose		 Lung blood vessels widened a little, an effect the authors called ‘modest and short-lived’, and there were no side effects17.
Petkov 2003, study comparing each patient with their own starting values, with no separate control group People with severe primary pulmonary hypertension 8 One 100 µg test dose, then 200 µg a day as four inhalations
Inhaled · 24 weeks		 Average lung artery pressure fell from 59 to 46 mmHg after 3 months, and the 6-minute walk distance rose by 113 m at 12 weeks (P < 0.01 for both)18.
Domschke 1978, dose study in healthy volunteers Healthy volunteers 4 0.6, 1.3 and 3.3 pmol/kg per minute
Drip into a vein (IV) · Three 30-minute infusions		 Even the smallest dose raised blood VIP well above normal; the highest slightly raised blood sugar, fatty acids and calcium, increased the pulse and caused skin flushing19.

Studies, animals and users: kept apart

Doses below are what studies used or what a label says. They are not advice, and gray-market products may not contain what their label says.

In human studies

IV: in COVID-AIV, 12-hour infusions of 50, 100 and 150 pmol/kg per hour on 3 successive days14; in TESICO, a 12-hour infusion each day for 3 days, targeting 600, 1,200 and 1,800 pmol/kg on days 1, 2 and 38. A 1978 volunteer study infused 0.6, 1.3 and 3.3 pmol/kg per minute, each for 30 minutes19. Inhaled: a single 100 µg dose in pulmonary hypertension17; 200 µg a day by mesh nebulizer, as two 100 µg doses 30 minutes apart, for 7 to 14 days in COVID-199. Nasal spray: 50 µg four times a day, later reduced, in the 2013 open-label mold-illness study10. Injection into the penis: 25 µg VIP with 1 or 2 mg phentolamine per injection in trials13; the Swedish label for the 25 µg/2 mg product says injections should not exceed once a day or 3 times a week7. VIP alone was tested at 200 or 400 pmol per penile injection16. We found no human study of VIP injected under the skin, the route many community pages list.

In animal studies

Mice with a chemically induced, Crohn’s-like colitis: 1 nmol of VIP per mouse, as a single dose 12 hours after the colitis was triggered or every other day21. An arthritis study reported benefit, but its abstract gives no dose22.

What users report Anecdotal · not validated · not a recommendation

A community dosing guide (dated 25 April 2026) lists 50 µg injected under the skin twice a day or 100 µg once a day, and nasal sprays of 50 µg per spray, 4 to 8 sprays a day. We found no controlled trial that tested these amounts.20

Half-life and how it is taken

Half-life
1.7 minutes after IV injection7In healthy men, VIP from an Invicorp dose had a half-life of 1.7 minutes after IV injection and 5.3 minutes after injection into the penis, according to the Swedish product information7. A 1978 study in four healthy volunteers found an average disappearance half-time of one minute after IV infusion19. We found no published half-life for nasal sprays or injections under the skin.
Routes
  • IV infusion (12-hour drips in COVID-19 lung-failure trials; human data)
  • Inhaled by nebulizer (small human studies in pulmonary hypertension and sarcoidosis, and COVID-19 trials)
  • Injection into the penis, combined with phentolamine (the approved use abroad, as Invicorp; human trials)
  • Nasal spray (sold by US compounding pharmacies for mold illness; small open-label studies only)
  • Injection under the skin (listed on community and seller pages; no human study found)

Invicorp: the injection approved in Sweden

Invicorp is a prescription injection into the penis for erectile dysfunction in adult men, first approved in Sweden in May 2015, and its product information was last revised on 9 July 20267. Each dose is one 0.35 mL ampoule holding 25 µg of aviptadil and 2 mg of phentolamine mesilate, a second drug that widens blood vessels, so the label dose is for the pair, not for VIP alone7.

The label says injections should not exceed once a day or 3 times a week, that the first injections must be given by health care staff, and that men may inject at home after proper training7. It does not recommend Invicorp for children and notes that no formal studies were done in men over 75 or in people with kidney or liver problems7.

Its efficacy table lists two placebo-controlled studies7. In VP004 (238 patients), erections suitable for penetration followed 74% of 2,272 active injections and 12% of 451 placebo injections; in VP005 (105 patients), the figures were 73% of 1,017 and 13% of 2077. The active injections held 25 µg of VIP with either 1.0 or 2.0 mg of phentolamine7.

IV drips in COVID-19 lung failure

Two US trials gave aviptadil, lab-made VIP, as 12-hour drips into a vein on 3 days in people in hospital with COVID-19 lung failure814. They set doses in picomoles per kilogram of body weight (pmol/kg), a unit that counts molecules rather than weighing them814.

The larger trial, TESICO, found no benefit, and a 2025 review that pooled two randomized trials of aviptadil in acute respiratory distress syndrome found no survival benefit (odds ratio 1.01, p = 0.93)823. FDA declined to authorize IV aviptadil for emergency use in COVID-19 in November 2021 and again in July 20222425.

A 2022 list from India’s drug regulator includes an aviptadil injection, 15 µg per mL vial, approved on 29 April 2022 for restricted emergency use in severe COVID-19 with acute respiratory distress syndrome; the list gives no dose, and we did not check the approval’s current status26.

Pemziviptadil (PB1046) is a different molecule, a long-acting VIP analogue, which a 2020 COVID-19 trial gave as weekly injections under the skin before the company stopped it1. Its doses do not carry over to VIP.

Inhaled VIP: COVID-19 and other lung studies

In COVID-19, the largest inhaled trial with reported results was the aviptadil arm of the US I-SPY COVID trial, which had no placebo and was stopped for futility after 118 patients; its results come from a press release, and we found no journal paper on them2. The only placebo-controlled inhaled trial with published results that we found is the 80-person trial in Turkey, which a drug company funded9. Two other placebo-controlled trials, of 144 and 83 people, were stopped early and had posted no results as of 7 October 202634.

Outside COVID-19, the inhaled studies are small. The two pulmonary hypertension studies in the table, of 20 and 8 people, had no separate control group1718. An open study of 20 people with sarcoidosis, a disease that forms clumps of immune cells, often in the lungs, gave nebulized VIP for 4 weeks at a dose its abstract does not state27. A 34-person placebo-controlled trial of inhaled VIP in severe COPD (chronic obstructive pulmonary disease) ran from 2003 to 2006, but its registry record gives neither the dose nor any results5.

The compounded nasal spray

In the US, VIP nasal spray comes from compounding pharmacies, on prescription1128. One pharmacy says it is mainly used for chronic inflammatory response syndrome (CIRS), an illness its proponents tie to water-damaged buildings, and that the spray has not undergone FDA review for safety, effectiveness or quality1028.

Its dose comes from small studies with no placebo group1011. In the main one, 20 adults whose CIRS had not cleared with earlier treatment used 50 µg four times a day for at least 18 months10. A 2024 review of CIRS treatments rated this and the two other VIP studies it found, a 14-person case series and another open-label study, as Level IV, meaning single nonexperimental studies11.

The 2013 authors said a placebo-controlled trial had begun, but we found no registry record of it, and no trial of VIP for CIRS was listed on ClinicalTrials.gov as of 7 October 20261029.

Questions people ask

How much VIP peptide should I take?

No dose is established for mold illness or the other uses VIP is sold for online; the main nasal-spray study gave 50 µg four times a day to 20 people with no placebo group10. The only label dose we found is for Sweden’s Invicorp, an injection into the penis for erectile dysfunction that pairs 25 µg of aviptadil with 2 mg of phentolamine7. VIP is not FDA-approved, so any decision about using it belongs with a licensed prescriber6.

What is the dose of VIP nasal spray?

No nasal dose has been tested against a placebo for CIRS, the main use it is sold for1129. The 2013 open-label study gave 50 µg four times a day, and after six months its 20 patients changed how often they used it according to their symptoms10.

What dose of aviptadil was used for COVID-19?

US trials gave 12-hour IV drips on 3 days: 50, 100 and 150 pmol/kg per hour in one, and doses targeting 600, 1,200 and 1,800 pmol/kg in the larger one, which found no benefit814. Inhaled trials gave 100 µg three times a day, in a US trial arm stopped for futility, or 200 µg a day for 7 to 14 days, in an 80-person trial in Turkey29.

How often can Invicorp be used?

Sweden’s label says injections should not exceed once a day or 3 times a week7. Each injection is one ampoule of 25 µg aviptadil with 2 mg phentolamine, and the first injections must be given by health care staff7.

Can VIP be injected subcutaneously?

We found no human study of VIP injected under the skin. Invicorp, approved in Sweden, is injected into the penis together with phentolamine, and COVID-19 trials gave aviptadil as IV drips in hospital7814. Pemziviptadil, a different long-acting VIP analogue, was tested under the skin, but its doses do not apply to VIP1.

Go deeper

Sources

  1. 1Pemziviptadil (PB1046), a Long-acting, Sustained Release Human VIP Analogue, Intended to Provide Clinical Improvement to Hospitalized COVID-19 Patients at High Risk for Rapid Clinical Deterioration and Acute Respiratory Distress Syndrome (ARDS) (NCT04433546) ClinicalTrials.gov, 11 Dec 2020. clinicaltrials.gov
  2. 2I-SPY COVID Trial Sponsored by Quantum Leap Healthcare Collaborative Suggests No Clinical Benefit with Addition of Nebulized ZYESAMI® (aviptadil) When Given by Mouth Inhalation in Critically Ill Patients with COVID-19 Quantum Leap Healthcare Collaborative via PR Newswire, 31 Mar 2022. prnewswire.com
  3. 3Inhaled ZYESAMI™ (Aviptadil Acetate) for the Treatment of Severe COVID-19 (NCT04360096) ClinicalTrials.gov, 3 Feb 2023. clinicaltrials.gov
  4. 4Inhaled Aviptadil for the Treatment of COVID-19 in Patients at High Risk for ARDS (NCT04536350) ClinicalTrials.gov, 18 Jan 2024. clinicaltrials.gov
  5. 5Vasoactive Intestinal Peptide in COPD (NCT00464932) ClinicalTrials.gov, 24 Apr 2007. clinicaltrials.gov
  6. 6Drugs@FDA via openFDA: search for active ingredient aviptadil (no matches) U.S. Food and Drug Administration (openFDA), 6 Oct 2026. api.fda.gov · data query
  7. 7Invicorp (injektionsvätska, lösning 25 mikrogram/2 mg): produktresumé (summary of product characteristics, Swedish) Evolan Pharma AB via FASS (Sweden), 9 Jul 2026. fass.se
  8. 8Intravenous aviptadil and remdesivir for treatment of COVID-19-associated hypoxaemic respiratory failure in the USA (TESICO): a randomised, placebo-controlled trial The Lancet Respiratory Medicine, Sep 2023. pubmed.ncbi.nlm.nih.gov
  9. 9Inhaled Aviptadil Is a New Hope for Recovery of Lung Damage due to COVID-19 Medical Principles and Practice, 2025. pmc.ncbi.nlm.nih.gov
  10. 10Vasoactive intestinal polypeptide (VIP) corrects chronic inflammatory response syndrome (CIRS) acquired following exposure to water-damaged buildings Health (Scientific Research Publishing), Mar 2013. scirp.org
  11. 11Chronic inflammatory response syndrome: a review of the evidence of clinical efficacy of treatment Annals of Medicine and Surgery, Dec 2024. pmc.ncbi.nlm.nih.gov
  12. 12Intracavernosal injection of aviptadil and phentolamine for refractory erectile dysfunction The Journal of Sexual Medicine, 10 May 2025. pubmed.ncbi.nlm.nih.gov
  13. 13Treating men with predominantly nonpsychogenic erectile dysfunction with intracavernosal vasoactive intestinal polypeptide and phentolamine mesylate in a novel auto-injector system: a multicentre double-blind placebo-controlled study BJU International, Feb 1999. pubmed.ncbi.nlm.nih.gov
  14. 14The Use of IV Vasoactive Intestinal Peptide (Aviptadil) in Patients With Critical COVID-19 Respiratory Failure: Results of a 60-Day Randomized Controlled Trial Critical Care Medicine, 1 Nov 2022. pmc.ncbi.nlm.nih.gov
  15. 15AWMSG Secretariat Assessment Report: aviptadil/phentolamine mesilate (Invicorp) 25 micrograms/2 mg solution for injection, reference number 3435 All Wales Therapeutics and Toxicology Centre, May 2017. awttc.nhs.wales
  16. 16A clinical trial of intracavernous vasoactive intestinal peptide to induce penile erection The Journal of Urology, Feb 1990. pubmed.ncbi.nlm.nih.gov
  17. 17Inhalation of vasoactive intestinal peptide in pulmonary hypertension European Respiratory Journal, Nov 2008. pubmed.ncbi.nlm.nih.gov
  18. 18Vasoactive intestinal peptide as a new drug for treatment of primary pulmonary hypertension Journal of Clinical Investigation, May 2003. pubmed.ncbi.nlm.nih.gov
  19. 19Vasoactive intestinal peptide in man: pharmacokinetics, metabolic and circulatory effects Gut, Nov 1978. pubmed.ncbi.nlm.nih.gov
  20. 20VIP Dosage Chart: 50mcg SubQ AM/PM Protocol (2026) The Peptide Catalog, 25 Apr 2026. thepeptidecatalog.com
  21. 21Therapeutic effects of vasoactive intestinal peptide in the trinitrobenzene sulfonic acid mice model of Crohn’s disease Gastroenterology, Apr 2003. pubmed.ncbi.nlm.nih.gov
  22. 22Vasoactive intestinal peptide prevents experimental arthritis by downregulating both autoimmune and inflammatory components of the disease Nature Medicine, May 2001. pubmed.ncbi.nlm.nih.gov
  23. 23Aviptadil Therapy in Acute Respiratory Distress Syndrome Patients: A Systematic Review and Meta-analysis Indian Journal of Critical Care Medicine, Nov 2025. pubmed.ncbi.nlm.nih.gov
  24. 24US Food and Drug Administration Declines Emergency Use Authorization for ZYESAMI® (aviptadil) for Patients with Critical COVID-19 with Respiratory Failure NRx Pharmaceuticals via PR Newswire, 4 Nov 2021. prnewswire.com
  25. 25FDA Declines Emergency Use Authorization for ZYESAMI® (aviptadil) for subgroup of Patients with Critical COVID-19 at immediate risk of death from respiratory failure despite treatment with approved therapy, including remdesivir NRx Pharmaceuticals via PR Newswire, 1 Jul 2022. prnewswire.com
  26. 26List of new drugs approved in the year 2022 till date Central Drugs Standard Control Organisation, India, 2022. cdsco.gov.in
  27. 27Inhaled vasoactive intestinal peptide exerts immunoregulatory effects in sarcoidosis American Journal of Respiratory and Critical Care Medicine, 15 Aug 2010. pubmed.ncbi.nlm.nih.gov
  28. 28VIP (Vasoactive Intestinal Peptide) nasal spray, compounded medication page Strive Pharmacy (vendor), accessed 7 Oct 2026. strivepharmacy.com (seller page, deliberately not linked)
  29. 29ClinicalTrials.gov search: chronic inflammatory response syndrome, mold illness, water-damaged building or biotoxin (5 records, none testing VIP) ClinicalTrials.gov, accessed 7 Oct 2026. clinicaltrials.gov

Not medical advice. Talk to a licensed clinician before using any drug. Report an error.