NAD+ and NAD+-related compounds can be taken in several ways, including oral capsules, powders, sublingual preparations, 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.
Intravenous NAD+ has been studied under more limited and strictly defined clinical conditions.
NAD+ preparations for subcutaneous and intramuscular administration are commercially available, yet their frequency of use and administration regimens have not been standardised 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 injectable NAD+ differ in their pharmacokinetics, the scope 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 use 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 the administration of 1,200 mg daily of NR or NMN. [1]
Blood NAD+ levels increased gradually.
After about two weeks of regular daily use, the values were approaching a plateau.
Once supplementation had ended, NAD+ levels also gradually decreased.
Changes in NAD+ levels in the brain occurred even more slowly.
A measurable increase in NAD+ levels in the brain became apparent after around four weeks of daily use. [1]
This gradual increase and subsequent slow decline help to 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 sustained excess following a single dose, which would clearly justify replacing daily use with a single dose once a week.
A similar pattern emerges in other important studies on precursors.
In a 60-day study of different doses of NMN, daily administration was used throughout the study period. [2]
In an eight-week study of different doses of NR, daily administration was also used. [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 trials is available.
intravenous NAD+
In the published studies, intravenously administered NAD+ was usually used in short, strictly defined courses, rather than as a treatment repeated indefinitely.
In one randomised 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 clearly in terms of dosage.
However, they shared one important feature: they both involved short runs of consecutive days of administration.
None of these studies assessed 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 considerably smaller.
Commercial protocols may recommend daily injections, injections every other day, or several injections a week.
However, no controlled human trials have been identified that would establish a single optimal frequency for these routes of administration.
For this reason, commercially available NAD+ injection regimens should be regarded primarily as practices employed by specific providers or specialists, rather than as standardised regimens based on robust clinical evidence.
Nor can frequency be considered in isolation from dose and formulation.
A smaller amount taken every day is not automatically equivalent to a larger amount taken once or twice a week.
In the absence of pharmacokinetic data for a specific route of administration, such regimens cannot simply be converted on the basis of the total weekly dose in milligrams.
How should NAD+ be taken – orally, sublingually or by injection?
Each route of administration uses a different pathway in the body.
These forms should not be regarded as interchangeable simply because they are all sold within the broad category of NAD+-related products.
Capsules, tablets and oral powders
Oral NAD+ products are swallowed and pass through the digestive tract.
Most clinical trials 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.
The powders contain the same type of compound in a form that is not enclosed in a capsule 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 research has 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 administration.
Sublingual NAD+
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 the partial bypass of the gastrointestinal tract and first-pass metabolism.
Sublingual administration is a well-known pharmaceutical strategy for certain medicines.
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 characterised than standard oral use of NR or NMN.
Commercial instructions specifying how long a preparation should be held under the tongue, how often it should be used, or what quantity corresponds to an oral capsule are therefore usually specific to the formulation in question, rather than being based on standardised comparative clinical trials.
NAD+ administered subcutaneously and intramuscularly
NAD+ for injection may be available as a ready-to-use solution, a freeze-dried powder, a cartridge or a pen-based product.
Subcutaneous administration involves injecting the preparation into the fatty tissue beneath the skin.
Intramuscular administration means injecting it into a muscle.
Some freeze-dried preparations require reconstitution before use.
However, the method of preparation, concentration, solvent, storage requirements and instructions for administering the injection may vary between individual formulations.
For this reason, general protocols available online should not be used in place of instructions relating to a specific formulation.
Anyone who has been prescribed a product for self-injection should receive instructions on the specific product and practical training from a suitably qualified doctor or pharmacist.
This route of administration also has a much smaller body of controlled human trials than oral NR or NMN.
Commercial availability should therefore not be equated with clinical validation of a specific dosage for a given route of administration.
intravenous NAD+
An intravenous infusion delivers NAD+ directly into the bloodstream via a catheter inserted into a vein.
Administration is usually carried out by trained medical staff.
Unlike oral supplements, IV therapy completely bypasses the absorption process in the gastrointestinal tract.
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 centre’s protocol.
The published clinical trials used specific, controlled regimens. However, these should not automatically be applied to commercial infusions offered for wellness purposes.
An oral capsule cannot be directly converted into an intravenous preparation.
Similarly, the milligram dose of NAD+ administered intravenously should not be regarded as a direct equivalent of an oral dose of NR or NMN.
These routes have fundamentally different pharmacokinetic properties.
How often is NAD+ IV therapy usually repeated?
This is one of the areas in which commercial practice goes well beyond the scope of published clinical evidence.
The available studies provide examples of short courses of treatment.
However, they do not set out a verified long-term maintenance plan.
In a randomised trial on heart failure, participants were given NAD+ intravenously every day for seven consecutive days. [4]
In a retrospective analysis of the clinical use of NAD+, it was administered daily for four consecutive days. [5]
None of these studies assessed whether repeating such series on a weekly, monthly or quarterly basis, or for an indefinite period, brings any additional benefits.
Nor has the optimal interval between successive sets been established.
Commercial clinics may offer NAD+ under a variety of different schemes.
Some offer one-off sessions.
Others offer several more fill-ups.
Some then recommend regular maintenance sessions, such as weekly or monthly appointments.
These diagrams may reflect local clinical practice, the preferences of a particular specialist, or the structure of a commercial programme.
However, they should not be presented as timetables validated by controlled trials.
A systematic review from 2026 found no eligible controlled clinical trials evaluating intravenous or intramuscular administration of NAD+ specifically for general wellness or anti-ageing purposes. [6]
That is an important finding.
This means that, despite the widespread commercial availability of NAD+ IV, the current evidence does not specify how often healthy individuals should undergo such treatment to boost energy levels, promote longevity, aid recovery or improve 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 can be promoted as being for energy.
Another may be offered as an anti-ageing solution.
A more intense, short set can be presented as supporting recovery.
Published research does not currently support such goal-dependent differences.
Most clinical trials use a single fixed dosing regimen throughout the duration of the experiment.
The regimen is selected as part of the study design rather than being individually tailored based on whether the participant expects higher energy, better recovery, slower ageing, improved cognitive function or any other effect.
Previously discussed NR and NMN research used daily dosing when assessing various outcomes. [1–3]
They included NAD+ biomarkers, physical fitness, cardiovascular parameters, neurological endpoints and other functional measurements.
The dosing frequency generally remained constant despite varying study objectives.
The situation is similar in limited studies on 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 correct regimen for longevity.
Anti-ageing
There is no verified dosage of NAD+ specifically intended to slow down the ageing process in humans.
Daily intake of oral precursors is the most thoroughly researched way to maintain elevated NAD+ biomarkers.
However, higher NAD+ levels alone do not prove slower biological ageing or a longer lifespan in humans.
Weekly or monthly maintenance NAD+ infusions promoted as anti-ageing have not been verified in controlled comparative studies involving humans.
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-boosting agents.
However, there is no controlled evidence showing that a specific daily, weekly, or intravenous regimen should be chosen specifically 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 schedule specifically for energy.
Regeneration
Regeneration-focused NAD+ protocols are also frequently found in the wellness sector.
Also here, controlled trials did not show that regeneration requires a different administration frequency than other objectives.
The clinic may use a short, intensive course for practical reasons.
However, such a regime should be described as an established practice rather than as a method with proven superiority in terms of recovery.
So the general rule is simple.
Research provides data regarding administration schedules of specific tested compounds and protocols.
They do not justify ascribing different NAD+ application frequencies solely on the basis of a change in marketing objective.
Comparison of the main NAD+ administration methods
| Administration method | What is usually served | Typical frequency in research | The strength of the evidence regarding frequency |
|---|---|---|---|
| Oral NR | NAD+ precursor | Every day | Relatively strong data from human studies [1,3] |
| Oral NMN | NAD+ precursor | Every day | Relatively strong human trial data [1,2] |
| Oral powder | Usually NR or NMN | Usually every day, if the data are extrapolated from studies of the given compound | There are data for the compound; limited powder-specific data |
| Sublingually | NAD+ or precursor | Depending on the product | Restricted dedicated benchmark data |
| NAD+ IV | Intact NAD+ | Short series of consecutive days in the available studies [4,5] | Limited and application-specific |
| NAD+ intramuscularly | Intact NAD+ | Variables in commercial practice | No established, standardised frequency |
| NAD+ subcutaneously | Intact NAD+ | Variables in commercial practice | No established, standardised frequency |
| NAD+ pen | Usually compounded liquid NAD+ | Depending on the device/protocol | Very limited standardised clinical data |
The most important distinction is that a frequently encountered commercial scheme does not necessarily have to be a clinically verified one at the same time.
Can NAD+ administration methods be used interchangeably?
Not automatically.
Different NAD+ related products contain different molecules.
The capsule may contain NR or NMN, but not NAD+ itself.
However, the injection preparation may contain intact NAD+.
The sublingual formulation may contain both NAD+ and one of its precursors.
This means that changing from one form to the other is not simply a matter of matching the number of milligrams.
For example, 500 mg of NMN does not mean the same chemical exposure as 500 mg of NAD+ administered intravenously.
NMN must first enter the NAD+ biosynthesis pathways.
Intravenous NAD+, on the other hand, goes directly into the circulation.
Absorption, metabolism, tissue distribution and the transformation processes of these compounds are different.
The same issue applies to the comparison of the oral, sublingual, intramuscular and subcutaneous routes.
The parenteral route does not automatically have a straightforward 1:1 conversion factor compared to the oral product.
Establishing direct equivalence would require comparative pharmacokinetic studies.
For many NAD+ formulations, such data is still lacking.
Frequently asked questions about taking NAD+
How often should NAD+ be taken?
The answer depends on the form. In human studies involving oral precursors of NR and NMN, daily administration has by far been used most frequently. Published IV NAD+ studies, on the other hand, have primarily used short series of consecutive days. Controlled trials have not established a single standardised frequency for subcutaneously or intramuscularly administered NAD+.
Should NR or NMN be taken daily?
Daily administration is the regimen most frequently used in human NR and NMN trials.
Pharmacokinetic studies suggest that blood NAD+ levels increase gradually and may approach a plateau after about two weeks of regular use. However, the increase of NAD+ in the brain may require more time. [1]
Weekly or intermittent regimens have not been comparatively studied to a similar extent.
How long do oral NAD+ precursors take to increase NAD+ levels?
One phase I study found that blood NAD+ levels progressively increased and approached a plateau after about two weeks of daily NR or NMN supplementation, whereas measurable changes in brain NAD+ appeared after about four weeks. [1]
These data come from a small study and should not be treated as universal for 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 NR and NMN studies use daily supplementation, so there is not enough data to state that weekly administration provides the same NAD+ exposure or similar results.
How often should NAD+ IV drips be administered?
There is no verified frequency for maintenance NAD+ infusions in wellness or anti-ageing applications.
Published research provides 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 protocols.
Is one NAD+ IV session enough?
There is no controlled evidence confirming that a single IV session provides lasting wellness, anti-ageing or recovery benefits.
Existing published protocols have typically involved multiple administrations over several consecutive days rather than a single isolated infusion as a verified long-term intervention.
Can NAD+ be administered subcutaneously?
Commercial subcutaneous NAD+ preparations exist, however controlled human trials regarding standardised subcutaneous doses, frequency, pharmacokinetics and long-term outcomes remain limited.
Therefore, product-specific instructions provided by the responsible doctor or pharmacy should take precedence.
Is sublingual NAD+ better than a capsule?
This has not been settled.
Sublingual administration can theoretically bypass some 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 matching doses.
Do you have to take NAD+ in the morning?
Published human studies have not definitively shown the advantage of morning use.
Some commercial products recommend taking them in the morning due to the involvement of NAD+ in energy metabolism, but the best 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-ageing purposes has been established.
Daily use of precursors has been used in research to maintain elevated NAD+ biomarkers, but no study shows that any specific daily, weekly or monthly NAD+ regimen slows down ageing in humans.
Is NAD+ used differently for increasing energy and recovery?
Commercial protocols may vary depending on the stated 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 practice of a given provider than from direct comparative clinical trials.
Limitations of current research
The strongest data regarding dosing frequency relates to oral NAD+ precursors, rather than directly to NAD+.
NR and NMN have been studied repeatedly with daily use.
However, even the detailed pharmacokinetic observation, according to which blood NAD+ approaches a plateau after about two weeks and brain NAD+ increases more slowly, comes from a relatively small phase I study involving six healthy individuals and six individuals with Parkinson's disease. [1]
Larger and more varied studies would increase confidence regarding these precise timeframes.
Another limitation is intravenously administered NAD+.
Published studies have used short, supervised courses, but no controlled trial has established the frequency of long-term, repeated therapies for anti-aging, energy boosting, recovery or general wellness.
Therefore, the weekly and monthly infusion regimens found in commercial clinics remain largely practice-based.
Even bigger gaps in the evidence concern subcutaneously and intramuscularly administered NAD+.
Commercial preparations are available, but standardised dosing frequency, pharmacokinetics characteristic of the given route of administration, and long-term safety have not been established in robust controlled studies involving humans.
Sublingual NAD+ related products also lack strong direct comparative data.
It has not been shown in a reliable human study how their absorption or frequency of use compares to conventional oral NR or NMN.
Another limitation is goal-based marketing.
Research typically does not assign different frequencies depending on whether the goal is energy, recovery, cognitive support or anti-aging.
Usually, the same dosing schedule is applied and then various endpoints are measured.
Finally, individual 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 for educational and scientific-information purposes only. It does not constitute medical advice, individual recommendations regarding the method of administration, dosing schedule, instructions for performing injections, or a recommendation for the use of NAD+, NR, NMN, or any NAD+-related therapy.
The administration schedules discussed here describe 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-ageing, energy boosting, recovery, general wellness, or the treatment, prevention, or cure of diseases.
The scope of evidence differs significantly between oral precursors, sublingual products, intravenously administered NAD+, and subcutaneous and intramuscular preparations. Commercially recommended regimens may therefore reflect the practice of the manufacturer, clinic, or compounding pharmacy rather than protocols verified 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 randomised, 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 randomised, 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 ischaemic cardiomyopathy: A randomised, 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