NAD+ and NAD+-related compounds can be taken in several ways, including oral capsules, powders, sublingual formulations, intravenous infusions, and injections. Therefore, the question „How to take NAD+?” is more complex than it might initially seem. The answer largely depends on the form used. Oral NAD+ precursors, such as nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN), have a relatively well-developed base of human clinical research.
Intravenously administered NAD+ has been studied in more limited and strictly defined clinical settings.
NAD+ preparations for subcutaneous and intramuscular administration are commercially available; however, their frequency of use and dosing regimens have not been standardized in comparable controlled clinical trials.
In this guide, we compare the individual administration methods based on the dosing regimens and frequencies actually described in published studies.
We also separate evidence-based frameworks from practices stemming mainly from commercial protocols or established customs.
How often should NAD+ be taken or administered?
There is no single dosing frequency suitable for all NAD+-related products.
Oral NR and NMN, intravenous NAD+, and NAD+ injections differ in pharmacokinetics, the body of available evidence, and the practical reasons why they are used with a specific frequency.
Oral NAD+ precursors: NR and NMN
For oral NR and NMN, daily administration is by far the most commonly studied regimen.
A particularly important Phase I pharmacokinetic study evaluated changes in NAD+ levels in both the blood and the brain during treatment with 1,200 mg per day of NR or NMN. [1]
Blood NAD+ levels increased gradually.
After about two weeks of regular daily use, the values began to level off.
After supplementation ended, NAD+ levels also gradually decreased.
Changes in NAD+ levels in the brain occurred even more slowly.
A measurable increase in NAD+ in the brain became apparent after about four weeks of daily use. [1]
This gradual increase and subsequent slow decline help explain why virtually all major human studies on NR and NMN have used daily administration rather than occasional or weekly use.
Regular exposure appears to be necessary to maintain the elevated levels of NAD+-related biomarkers observed in these studies.
The body does not appear to accumulate a large and persistent excess after a single dose that would clearly justify replacing daily use with a once-weekly dose.
A similar pattern emerges in other important studies on precursors.
In a 60-day study of various NMN doses, daily administration was used throughout the entire study period. [2]
An eight-week study of different doses of NR also used daily administration. [3]
These studies do not prove that daily use is the only possible regimen.
However, they show that it is precisely for this method of administration that the most direct data from human studies are available.
NAD+ administered intravenously
In published studies, intravenous NAD+ was typically administered in short, strictly defined courses rather than as an indefinite, repeated therapy.
In one randomized clinical trial involving patients with heart failure, 10 mg of NAD+ was administered intravenously once daily for seven consecutive days. [4]
A separate retrospective analysis of the clinical practice of IV therapy evaluated 500 mg of NAD+ administered intravenously once daily for four consecutive days. [5]
The two protocols differed very significantly in terms of dosage.
However, they shared one important characteristic: they consisted of short series of consecutive days of administration.
None of these studies evaluated a single, one-off session as a definitive form of therapy.
Nor has it been established that weekly, monthly, or quarterly NAD+ infusions are validated regimens for long-term maintenance therapy.
NAD+ administered subcutaneously and intramuscularly
In the case of self-administered subcutaneous or intramuscular NAD+, the evidence base is much smaller.
Commercial protocols may recommend daily injections, injections every other day, or several injections per week.
However, no controlled human studies were identified that established a single optimal frequency for these routes of administration.
For this reason, commercially available NAD+ injection regimens should be viewed primarily as practices used by specific providers or specialists, rather than as standardized regimens based on strong clinical evidence.
Frequency also cannot be considered independently of dose and formulation.
A smaller amount given daily is not automatically equivalent to a larger amount given once or twice a week.
Without pharmacokinetic data for a specific route of administration, such regimens cannot simply be calculated based on the total weekly number of milligrams.
How should NAD+ be taken—orally, sublingually, or by injection?
Each method of administration takes a different route through the body.
These forms should not be considered interchangeable simply because they are all sold under the broad category of NAD+ products.
Capsules, tablets, and oral powders
Oral NAD+ products are swallowed and pass through the gastrointestinal tract.
Most clinical studies in this category focus on NAD+ precursors rather than the intact NAD+ molecule.
The most thoroughly studied examples are NR and NMN. [1–3]
Capsules and tablets contain a predetermined amount of the active ingredient.
Powders contain the same type of compound in a form that is not encapsulated and usually need to be measured out before use.
Some commercial products suggest taking NAD+ precursors in the morning.
Others recommend taking them with a meal or on an empty stomach.
However, published studies have not shown that any specific time of day consistently leads to greater NAD+ increases or better clinical outcomes.
The best-documented element is regular, daily use, rather than a specific time of intake.
NAD+ sublingually
Sublingual products are placed under the tongue and left to dissolve.
The assumed mechanism is absorption through the oral mucosa.
Theoretically, this may allow for a partial bypass of the gastrointestinal tract and first-pass metabolism.
Sublingual administration is a well-known pharmaceutical strategy for certain drugs.
However, this does not automatically mean better absorption of NAD+, NR, or NMN.
No direct superiority of sublingual NAD+-related products over standard swallowed precursor capsules has been established in dedicated controlled human studies.
Therefore, sublingual administration remains less characterized than conventional oral use of NR or NMN.
Commercial instructions specifying how long the preparation should be held under the tongue, how often to use it, or what amount corresponds to an oral capsule are therefore usually specific to a given formulation rather than based on standardized comparative clinical studies.
NAD+ subcutaneously and intramuscularly
Injectable NAD+ may be available as a ready-to-use liquid, lyophilized powder, cartridge, or pen product.
Subcutaneous administration means the introduction of a preparation into the adipose tissue under the skin.
Intramuscular injection means introducing it into a muscle.
Some lyophilized products require reconstitution before administration.
However, preparation method, concentration, solvent, storage requirements, and injection instructions may vary between compounded products.
For this reason, general protocols available online should not replace the instructions for a specific formulation.
Every person who has been prescribed a medication for self-injection should receive product-specific instructions and hands-on training from a properly qualified physician or pharmacist.
This route of administration also has a significantly smaller base of controlled human studies than oral NR or NMN.
Commercial availability should therefore not be equated with the clinical validation of a specific dosage for a given route of administration.
NAD+ administered intravenously
An intravenous infusion delivers NAD+ directly into the bloodstream through a catheter placed in a vein.
Administration is usually performed by trained medical personnel.
Unlike oral supplements, IV therapy completely bypasses the gastrointestinal absorption process.
The infusion is usually administered gradually.
A commercial session can last from less than an hour to several hours, depending on the volume, concentration, infusion rate, and the facility's protocol.
The published clinical studies used specific, controlled regimens. However, these should not be automatically applied to commercial infusions offered for wellness purposes.
An oral capsule cannot be directly converted to an intravenous formulation.
Similarly, the milligram amount of NAD+ administered intravenously should not be considered a direct equivalent of an oral dose of NR or NMN.
These pathways have fundamentally different pharmacokinetics.
How often is IV NAD+ therapy typically repeated?
This is one of the areas in which commercial practice goes well beyond the scope of published clinical evidence.
Available studies provide examples of short series of administrations.
However, they do not specify a verified long-term maintenance schedule.
In a randomized trial on heart failure, participants received NAD+ intravenously every day for seven consecutive days. [4]
In a retrospective analysis of commercial NAD+ use, it was administered daily for four consecutive days. [5]
None of these studies evaluated whether repeating such series every week, month, quarter, or indefinitely provides additional benefits.
The optimal interval between consecutive sets has not been determined either.
Commercial clinics may offer NAD+ through a variety of treatment regimens.
Some offer single sessions.
Others offer several additional fill ports.
Some then recommend periodic maintenance sessions, such as weekly or monthly visits.
These diagrams may reflect local clinical practice, the preferences of a particular specialist, or the design of a commercial program.
However, they should not be presented as schedules confirmed in controlled studies.
A 2026 systematic review did not identify any eligible controlled clinical trials evaluating intravenous or intramuscular administration of NAD+ specifically for general wellness or anti-aging purposes. [6]
This is an important finding.
This means that despite the wide commercial availability of NAD+ IV, current evidence does not determine how often healthy individuals should use such administration to increase energy, support longevity, recovery, or general well-being.
In the case of proposals for repeated NAD+ infusions, it is therefore reasonable to ask the supplier what evidence supports the recommended schedule.
This is of particular importance when the clinic proposes long-term, regularly repeated sessions.
Does the frequency depend on the goal, such as anti-aging, energy, or recovery?
Commercial NAD+ protocols are often divided by purpose.
One scheme may be promoted as intended for energy.
Another may be offered as an anti-aging solution.
A more intense, short set can be presented as supporting recovery.
Published research does not currently confirm such goal-dependent differences.
Most clinical trials use a single fixed dosing regimen throughout the duration of the experiment.
The regimen is chosen as part of the study design rather than individually tailored to whether the participant expects more energy, better recovery, slower aging, improved cognitive function, or another effect.
The previously discussed NR and NMN studies used daily dosing when evaluating various outcomes. [1–3]
These included NAD+ biomarkers, physical performance, cardiovascular parameters, neurological endpoints, and other functional measurements.
The dosing frequency usually remained constant despite various research objectives.
The situation is similar in limited studies regarding intravenous administration.
In the heart failure study, a single sequential-day regimen was used in a strictly defined group of patients. [4]
This does not mean that daily intravenous administration should be used to increase energy.
It also does not mean that monthly administration is the proper regimen for longevity.
Anti-aging
There is no verified frequency of NAD+ administration specifically intended for slowing down the aging process in humans.
Daily oral administration of precursors is the best-studied method for maintaining elevated NAD+ biomarkers.
However, higher NAD+ levels alone do not prove slower biological aging or longer life in humans.
Weekly or monthly maintenance NAD+ infusions promoted as anti-aging have not been verified in controlled comparative human studies.
Energy
NAD+ plays a key role in cellular energy metabolism.
This biochemical function has significantly contributed to the marketing of NAD+ related products as energy-supporting agents.
However, there is no controlled evidence showing that a specific daily, weekly, or intravenous regimen should be chosen precisely for subjectively perceived energy.
Research on oral precursors primarily supports regular daily use to alter biomarkers associated with NAD+.
They do not establish a separate dosage regimen specifically intended for energy.
Regeneration
NAD+ protocols aimed at regeneration are also commonly found in the wellness sector.
Here, too, controlled studies have not shown that regeneration requires a different administration frequency than other goals.
The clinic may use a short, intensive series for practical reasons.
However, such a scheme should be described as an accepted practice rather than as a method with proven superiority in terms of regeneration.
Therefore, the general rule is simple.
Research provides data regarding administration schedules of specific tested compounds and protocols.
They do not justify assigning different frequencies of NAD+ use solely based on a change in the marketing goal.
Comparison of main NAD+ administration methods
| Route of administration | What is usually served | Typical frequency in research | The strength of the evidence regarding frequency |
|---|---|---|---|
| Oral NR | NAD+ precursor | Every day | Relatively strong human trial data [1,3] |
| Oral NMN | NAD+ precursor | Every day | Relatively strong human trial data [1,2] |
| Oral powder | Usually NR or NMN | Usually daily, if data are extrapolated from studies of a given compound | Data exist for the compound; limited data specific to the powder form |
| Sublingually | NAD+ or precursor | Depending on the product | Limited dedicated benchmark data |
| NAD+ IV | Intact NAD+ | Short series of consecutive days in available studies [4,5] | Limited and application-specific |
| NAD+ intramuscularly | Intact NAD+ | Variables in commercial practice | No established, standardized frequency |
| NAD+ subcutaneously | Intact NAD+ | Variables in commercial practice | No established, standardized frequency |
| NAD+ Pen | Typically, a formulated liquid NAD+ | Depending on the device/protocol | Very limited standardized clinical data |
The key distinction is that a commonly used commercial protocol is not necessarily a clinically validated one.
Can the different methods of administering NAD+ be used interchangeably?
Not automatically.
Different NAD+ products contain different molecules.
A capsule may contain NR or NMN, but not NAD+ alone.
The injectable formulation, on the other hand, may contain intact NAD+.
A sublingual formulation may contain both NAD+ and one of its precursors.
This means that converting from one form to another isn't simply a matter of adjusting the number of milligrams.
For example, 500 mg of NMN does not result in the same chemical exposure as 500 mg of NAD+ administered intravenously.
NMN must first enter the NAD+ biosynthesis pathways.
Intravenously administered NAD+ enters the bloodstream directly.
Absorption, metabolism, tissue distribution, and the transformation processes of these compounds are different.
The same issue applies to a comparison of the oral, sublingual, intramuscular, and subcutaneous routes.
A route of administration that bypasses the gastrointestinal tract does not automatically have a 1:1 conversion ratio with respect to the oral formulation.
Establishing direct equivalence would require comparative pharmacokinetic studies.
Such data is still lacking for many NAD+ formulations.
Frequently Asked Questions About Taking NAD+
How often should you take NAD+?
The answer depends on the form. In human studies involving oral NR and NMN precursors, daily administration was by far the most common approach. Published studies on IV NAD+, on the other hand, mainly used short series of consecutive days. Controlled studies have not established a single standardized frequency for subcutaneous or intramuscular administration of NAD+.
Should NR or NMN be taken daily?
Daily administration is the regimen most commonly used in human studies of NR and NMN.
Pharmacokinetic studies suggest that blood NAD+ levels rise gradually and may approach a plateau after about two weeks of regular use. However, it may take longer for NAD+ levels in the brain to increase. [1]
Weekly or intermittent regimens have not been studied comparatively to the same extent.
How long does it take for oral NAD+ precursors to increase NAD+ levels?
One Phase I study found that blood NAD+ levels gradually increased and approached a plateau after about two weeks of daily NR or NMN use, while measurable changes in NAD+ levels in the brain appeared after about four weeks. [1]
These data come from a small study and should not be considered applicable to every person or formulation.
Can NAD+ be taken once a week?
Weekly dosing of NAD+ precursors has not been adequately evaluated in controlled human studies.
Most published studies on NR and NMN involve daily administration; therefore, there is insufficient data to conclude that once-weekly administration provides the same exposure to NAD+ or similar results.
How often should NAD+ IV infusions be administered?
There is no verified frequency for NAD+ maintenance infusions in wellness or anti-aging applications.
Published studies provide examples of short series of consecutive days, including seven daily administrations in one heart failure study and four consecutive daily administrations in a commercial retrospective analysis. [4,5]
However, these studies do not establish weekly or monthly maintenance regimens.
Is one NAD+ IV session enough?
There is no controlled evidence to support the claim that a single IV session provides lasting benefits related to wellness, anti-aging, or recovery.
Existing published protocols typically involved repeated administration over several consecutive days, rather than a single, isolated infusion, as a validated long-term intervention.
Can NAD+ be administered subcutaneously?
Commercial NAD+ preparations for subcutaneous administration are available; however, controlled human studies on standardized subcutaneous doses, frequency of administration, pharmacokinetics, and long-term outcomes remain limited.
Therefore, instructions concerning a specific product provided by the physician or pharmacy responsible for it should take precedence.
Is sublingual NAD+ better than a capsule?
It has not been determined.
Sublingual administration can theoretically bypass part of the metabolism occurring in the gastrointestinal tract, but there is a lack of controlled human studies directly comparing sublingual NAD+ or its precursors with standard oral NR or NMN at corresponding doses.
Does NAD+ need to be taken in the morning?
Published studies involving humans have not conclusively shown the benefit of morning use.
Some commercial products recommend morning intake due to the role of NAD+ in energy metabolism, but the most well-documented importance is regular dosing rather than a specific time of day.
Should the frequency of NAD+ use be different in the case of anti-aging?
No verified frequency of NAD+ use specifically for anti-aging purposes has been established.
Daily use of precursors has been used in studies to maintain elevated NAD+ biomarkers, but no study shows that any specific daily, weekly, or monthly NAD+ regimen slows aging in humans.
Is NAD+ used differently to boost energy and support recovery?
Commercial protocols may vary depending on the declared purpose, but controlled studies have not established separate, evidence-based frequencies for energy, recovery, longevity, or similar wellness goals.
Goal-dependent regimens usually stem more from the given provider's practice than from direct comparative clinical trials.
Limitations of current research
The strongest data on frequency of use pertain to oral NAD+ precursors, rather than to NAD+ itself.
NR and NMN have been extensively studied with daily use.
However, even detailed pharmacokinetic observations—which show that NAD+ levels in the blood approach a plateau after about two weeks— while NAD+ levels in the brain increase more slowly, comes from a relatively small Phase I study involving six healthy individuals and six people with Parkinson’s disease. [1]
Larger and more diverse studies would provide greater certainty regarding this precise time frame.
The second limitation is NAD+ administered intravenously.
Published studies have used short, supervised series, but no controlled study has determined the frequency of long-term, repeated treatments for anti-aging, energy enhancement, recovery, or general wellness.
Therefore, the weekly and monthly infusion regimens found in commercial clinics remain largely practice-based.
There are even greater gaps in the evidence regarding NAD+ administered subcutaneously and intramuscularly.
Commercial preparations are available, but a standardized dosing regimen, route-specific pharmacokinetics, and long-term safety have not been established in robust controlled human studies.
Sublingual products containing NAD+ also lack strong direct comparative data.
No reliable human study has demonstrated how their absorption or frequency of use compares to that of conventional oral NR or NMN.
Another limitation is goal-based marketing.
Studies generally do not specify different frequencies depending on whether the goal is energy, recovery, cognitive function support, or anti-aging.
Typically, the same dosing regimen is used, and then various endpoints are measured.
Finally, the various routes of administration cannot be compared solely on the basis of the number of milligrams.
Oral NR, oral NMN, sublingual NAD+, subcutaneous NAD+, and intravenous NAD+ involve different compounds or different pharmacokinetic pathways.
No direct dose equivalence has been established between these formats.
Disclaimer
This article is intended solely for educational and scientific purposes. It does not constitute medical advice, individual recommendations regarding administration, dosing regimens, injection instructions, or recommendations for the use of NAD+, NR, NMN, or any NAD+-related therapy.
The dosing regimens discussed here describe the protocols used in specific published studies and should not be interpreted as approved or universally appropriate methods of use. NAD+ and its precursors are not approved by the FDA or the EMA for anti-aging, energy enhancement, recovery, general wellness, or the treatment, prevention, or cure of any disease.
The body of evidence varies significantly among oral precursors, sublingual products, intravenously administered NAD+, and subcutaneous and intramuscular formulations. Commercially recommended regimens may therefore reflect the practices of the manufacturer, clinic, or compounding pharmacy rather than protocols validated in controlled human trials.
References
[1] Berven, H., Svensen, M., Eikeland, H., Tvedten, N., Sheard, E. V., Amdahl Af Geijerstam, S., Søgnen, M., McCann, A., Arnsten, L., Årseth, O., Skjeie, V., Hjellbrekke, A., Skeie, G.-O., Torres Cleuren, Y. N., Nido, G. S., Haugarvoll, K., Riemer, F., Tzoulis, C., & Dölle, C. (2026). The NAD-brain pharmacokinetic study of NAD augmentation in blood and brain using oral precursor supplementation. iScience, 29(3), 114764. https://doi.org/10.1016/j.isci.2026.114764
[2] Yi, L., Maier, A. B., Tao, R., Lin, Z., Vaidya, A., Pendse, S., Thasma, S., Andhalkar, N., Avhad, G., & Kumbhar, V. (2022). The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: A randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial. GeroScience, 45, 29–43. https://doi.org/10.1007/s11357-022-00705-1
[3] Conze, D., Brenner, C., & Kruger, C. L. (2019). Safety and metabolism of long-term administration of NIAGEN (nicotinamide riboside chloride) in a randomized, double-blind, placebo-controlled clinical trial of healthy overweight adults. Scientific Reports, 9, 9772. https://doi.org/10.1038/s41598-019-46120-z
[4] American Journal of Cardiovascular Drugs. (2026). Effect of nicotinamide adenine dinucleotide on heart failure caused by ischemic cardiomyopathy: A randomized, placebo-controlled trial. American Journal of Cardiovascular Drugs. https://pmc.ncbi.nlm.nih.gov/articles/PMC12779688/
[5] Reyna, K., Heinzen, G., Patel, N., Ritter, M., Siojo, A., Legere, H., & Pojednic, R. (2026). Intravenous infusion of nicotinamide adenine dinucleotide (NAD+) versus nicotinamide riboside (NR): A retrospective tolerability pilot study in a real-world setting. Frontiers in Aging, 7, 1652582. https://doi.org/10.3389/fragi.2026.1652582
[6] Gallagher, C., & Emmanuel, O. O. (2026). NAD+ supplementation for anti-aging and wellness: A PRISMA-guided systematic review of preclinical and clinical evidence. Ageing Research Reviews, 116, 103057. https://doi.org/10.1016/j.arr.2026.103057