At sellers that list both, the nasal spray is usually the cheaper line — sometimes by fifty dollars, sometimes by one. What you are not told is the thing that would make that a bargain or a waste: how much of a charged dinucleotide sprayed onto the lining of your nose actually reaches your blood. Nobody has published that number in a person.
The prices, at sellers that publish both
These are the standing month-to-month rates read off each seller’s own pages in September 2026, scoped to the product each figure belongs to.
Trava Health charges $157.91 for the spray and $158.93 for the injection, both at a published 100 mg — a dollar and change apart, which turns the choice between needle and nose into a preference rather than a budget decision. Ascend Vitality lists $149 for a 900 mg spray, $179 for a 1,200 mg spray and $199 for a 1,000 mg injection. TeleZen MD lists $148 against $198, and System Labs $119 for the spray against $149 for an injection at a stated 1,000 mg. HealthSource is the outlier in both directions: $179 for the spray against $279 for the 1,000 mg injection, but billed every four weeks rather than monthly, which is thirteen charges a year.
Why the milligram figure flatters the spray
HealthSource states its spray as 300 mg/mL in a 15 mL bottle. That is 4,500 mg of material for $179, which divides out at about four cents a milligram — roughly a quarter of what a published injection milligram costs on the injection board, and about an eightieth of what a drip costs. It is also the least meaningful number on this page.
A milligram in a syringe goes under the skin, where the absorption question is largely a matter of rate. A milligram in a spray bottle lands on a mucous membrane, and everything after that — what crosses, what runs down the back of your throat and gets swallowed, what is cleared before it crosses at all — is unmeasured for this molecule. NAD⁺ is not a small neutral drug. It is a dinucleotide carrying phosphate groups, the kind of large charged molecule that mucosal delivery struggles with, and the sellers quoting you a bottle total are quoting you a purchase, not a dose.
What has actually been published on intranasal NAD⁺
We searched PubMed in September 2026. A search for “nasal spray” together with “nicotinamide adenine dinucleotide” returns zero records. Broadening to intranasal or nasal spray with NAD⁺ in the title or abstract, filtered to anything mentioning randomized, placebo, volunteers or participants, also returns zero.
Two control searches run the same day confirm the filter works rather than the probe being blocked: intranasal or nasal-spray studies mentioning randomization or placebo since 2020 return 1,732 records, and NAD⁺ studies mentioning randomization return 152. The searches are finding papers. There are no papers of this kind to find.
One study does exist on the route, and it is worth reading for what it is. A 2026 paper treated cultured human olfactory stem cells with NAD and gave intranasal NAD to mice whose sense of smell had been destroyed with zinc sulfate. NAD promoted the stem cells’ differentiation into olfactory sensory neurons, and the treated mice showed significant improvement in olfactory function and marked repair of the olfactory epithelium [1]. That is a smell-restoration experiment in rodents. Nothing in it concerns energy, aging or anybody’s subscription.
The injection is not winning this on evidence either
It would be easy to read the paragraph above as an argument for the needle. It is not. A PRISMA-guided systematic review published in early 2026 swept human and rodent intervention studies of NAD-related compounds from January 2010 to October 2025, identified 113 eligible studies, and found that no eligible outcomes trial had evaluated intravenous or intramuscular NAD⁺ itself for an anti-aging or wellness indication [2]. The route with the better-understood absorption still has nothing showing it produces a result.
The format with randomized human trials behind its biomarker claim is neither of these — it is the precursor you swallow, at a fraction of both prices.
How to choose between them anyway
If you have decided on one of these two routes, the questions worth asking are mundane and answerable. Does the seller publish a milligram figure for the specific product you are buying, or a figure that belongs to the other one? Is the plan billed monthly or every four weeks — the four-week cycle adds a thirteenth charge a year that no annual comparison on a seller’s own page will show you. And does the bottle size match the billing cycle, because HealthSource’s own copy says a bottle may last up to two months while the plan renews every four weeks.
Both routes arrive compounded, which means they are not FDA-approved and are not reviewed by the FDA for safety, efficacy or quality before they are dispensed. Beyond that, the spray avoids a needle and usually costs less at the same seller, while the injection at least does not add an unmeasured absorption step on top of an unproven one. Neither has an outcome trial. The nasal spray board lists the sprays we have verified, with the price scoped to the spray rather than borrowed from the injection next to it.