Overview
A coenzyme present in every living cell and central to energy metabolism and DNA repair. Although not a peptide, NAD+ appears throughout longevity research and is commonly catalogued alongside research peptides.
Mechanism of Action
NAD+ is an essential redox cofactor that shuttles electrons in glycolysis, the citric acid cycle and oxidative phosphorylation, making it foundational to ATP production.
It is a required substrate for sirtuins, a family of enzymes associated in published research with metabolic regulation and cellular stress response.
It is consumed by PARP enzymes during DNA damage repair, linking NAD+ availability to genomic maintenance.
Tissue NAD+ concentrations are reported to decline with age in multiple species, which is the observation motivating most of the current research interest.
Areas Being Studied
- Cellular ageing and mitochondrial function
- Metabolic health
- Neuroprotection and cognitive research
- Exercise capacity and recovery
Listing a research area does not imply efficacy, approval, or suitability for any use.
Research Summary
- Animal studies of NAD+ precursors such as nicotinamide riboside and nicotinamide mononucleotide report restoration of tissue NAD+ levels and improvements in several age-related metabolic markers.
- Human trials of oral precursors have consistently reported increases in blood NAD+ metabolites; functional outcome results have been more variable across studies.
- Research distinguishes between direct NAD+ administration and precursor supplementation, which differ substantially in bioavailability and pharmacokinetics.
- Long-term human outcome data is not yet established.
Potential Adverse Effects Reported in Research
- Infusion-related effects such as flushing, nausea, chest tightness and lightheadedness are commonly reported when NAD+ is administered rapidly.
- Oral precursors are generally reported as well tolerated in short-term human trials.
- Injection-site discomfort is frequently described.
- Long-term safety at supraphysiological levels is not established in published literature.
Reconstitution Basics
Research-grade NAD+ is often supplied as a lyophilised powder in higher milligram amounts than peptides, so reconstitution volumes are correspondingly larger.
Bacteriostatic water
Sterile water containing roughly 0.9% benzyl alcohol as a preservative, which inhibits bacterial growth in multi-access vials.
Sterile technique
Laboratory documentation describes disinfecting the stopper, using a fresh sterile needle for each access, and avoiding contact with non-sterile surfaces.
After reconstitution
Solutions are refrigerated, protected from light, and not subjected to repeated freeze–thaw cycles.
This section is educational background on laboratory handling. It is not an instruction or protocol.
Open the reconstitution calculator →Dosing & Reconstitution Guide
NAD+ is studied at far larger masses than peptides, and infusion protocols are rate-limited: too-rapid administration is the most consistently reported source of discomfort in the literature.
Protocol overview
- Administration rate, not just mass, determines reported tolerability.
- IV infusion protocols dominate the clinical literature; subcutaneous use appears mainly in practitioner reports.
- Flushing, chest tightness and nausea during administration are consistently reported and rate-related.
Dosing protocol — standard titration
| Phase | Reported dose | Notes |
|---|---|---|
| Session 1 | Low end of the cited rangeSlow rate; tolerability is the limiting factor. | Slow rate; tolerability is the limiting factor. |
| Sessions 2–5 | Stepwise increase toward the cited targetIncrease rate/mass only if prior session was uneventful. | Increase rate/mass only if prior session was uneventful. |
| Maintenance | Target dose weekly to monthlyProtocols vary widely between clinics and studies. | Protocols vary widely between clinics and studies. |
Dosing protocol — gradual titration
| Phase | Reported dose | Notes |
|---|---|---|
| Weeks 1–2 | Small subcutaneous amountsUsed where infusion is not the route studied. | Used where infusion is not the route studied. |
| Weeks 3–6 | Gradual increaseFlushing and nausea are the reported rate limiters. | Flushing and nausea are the reported rate limiters. |
| Ongoing | Lowest amount that remains tolerableNo consensus maintenance schedule exists. | No consensus maintenance schedule exists. |
Schedules summarise what appears in published studies, trial protocols or manufacturer documentation. They are reference material, not a recommendation.
Where to Buy Compounds & Supplies
External link. PepDex does not sell products and does not endorse any supplier.
Supplies needed
Lyophilised peptide vial
Sealed vial with an intact stopper and a legible mass label (mg or mcg).
Bacteriostatic water
Sterile water with ~0.9% benzyl alcohol, used where a vial will be accessed more than once. Sterile water for injection is used for single-access work.
Reconstitution syringe
A 1–3 mL syringe with a larger-gauge needle for drawing and transferring solvent.
Insulin syringe (U-100)
Fine-gauge syringe graduated in units; 100 units = 1 mL. Used for accurate small-volume measurement.
Alcohol prep pads
70% isopropyl swabs for disinfecting both vial stoppers before every access.
Sharps container
Rigid, puncture-resistant container for single-use needle disposal.
Refrigeration and light protection
2–8 °C storage plus an opaque box or the original carton for reconstituted vials.
Labels
Date of reconstitution, resulting concentration and compound name on every vial.
Reconstitution steps
- 01
Bring the vial to room temperature
Lyophilised powder is allowed to equilibrate out of the refrigerator before the stopper is pierced, which reduces condensation inside the vial.
- 02
Disinfect both stoppers
The peptide vial and the bacteriostatic water vial are each swabbed with 70% isopropyl alcohol and allowed to air dry.
- 03
Draw the calculated solvent volume
Solvent volume is chosen to produce a convenient concentration — the reconstitution calculator converts vial mass and solvent volume into concentration and syringe units.
- 04
Add the solvent slowly down the vial wall
The stream is directed against the glass rather than onto the powder cake. Peptides are shear-sensitive and direct jetting is avoided.
- 05
Dissolve without shaking
The vial is left to stand, then gently swirled or rolled. Shaking introduces foam and mechanical stress that can denature peptide chains.
- 06
Inspect the solution
Documentation describes checking for a clear, particle-free solution. Cloudiness, visible particulate or discolouration is treated as a failed preparation.
- 07
Label and refrigerate
The vial is labelled with compound, concentration and date, then stored at 2–8 °C protected from light.
Storage instructions
- Before reconstitution: lyophilised powder is kept sealed, dry and away from light; most suppliers specify refrigeration at 2–8 °C, with freezer storage for long-term holding.
- After reconstitution: refrigerated at 2–8 °C and used within the window described in the literature (commonly cited as ~14–28 days refrigerated).
- Protection from light: the vial is kept in its carton or an opaque container; repeated exposure to daylight is avoided.
- Handling: repeated freeze–thaw cycles are avoided, and vials are not left at room temperature between accesses.
- Integrity checks: any solution that becomes cloudy, discoloured or shows particulate is discarded rather than filtered.
Half-Life
Minutes (circulating NAD+)
Circulating NAD+ turnover is rapid; the relevant research measure is generally tissue NAD+ concentration rather than plasma half-life.
Storage
- Before reconstitution
- Powder stored cold and dry; NAD+ is hygroscopic and moisture-sensitive.
- After reconstitution
- Refrigerated after reconstitution; solutions are less stable than many peptides.
- Light protection
- Protected from light.
- Shelf-life considerations
- Short usable window is typically described relative to lyophilised peptides.
Frequently Asked Questions
References
- NAD+ metabolism and its roles in cellular processes during ageing
Nature Reviews Molecular Cell Biology, 2021
- Nicotinamide riboside supplementation in humans: a randomised trial
Nature Communications, 2018
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Glutathione
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Educational reference only. Figures are compiled from published research literature. PepDex does not provide medical advice, dosing recommendations, or instructions for use.