By Chloé Nefdt, Professional Nurse & Founder of IVgo
If you've Googled "NAD+ side effects" and ended up here, you've probably already scrolled through a dozen pages that fall into one of two camps: breathless marketing copy insisting NAD+ is as harmless as a glass of water, or alarmist forum posts from someone who once read a headline and now considers themselves an authority on coenzyme biochemistry.
Neither is helpful. And if you're spending money on a therapy that goes into your body - whether via IV drip, injection pen, or anything else - you deserve better than marketing fluff or secondhand panic.
I'm Chloé Nefdt, a SANC-registered Professional Nurse and the founder of IVgo. I administer NAD+ therapy in Cape Town and I've had this conversation with every single client who's sat across from me. This article is that conversation - the same honest, evidence-based rundown I give in person, with references you can actually check.
What NAD+ Therapy Actually Involves (Quick Version)
I've written a comprehensive guide to NAD+ therapy - what it is, how it works, the science behind it - in my complete NAD+ guide. If you haven't read that yet, I'd recommend it for the full picture.
The short version: NAD+ (nicotinamide adenine dinucleotide) is a coenzyme your body already produces. It's essential for energy metabolism, DNA repair, and cellular signalling. Your levels decline with age - significantly - and NAD+ therapy aims to restore them.
Traditionally, that meant sitting in a clinic for several hours while NAD+ was dripped intravenously. At IVgo, I offer NAD+ as a subcutaneous injection pen - a pre-loaded device you self-administer at home after I've trained you. Different delivery method, different side effect profile, and I'll break down both in this article.
Common Side Effects During IV NAD+ Infusion
Let's start with IV drip delivery, because most of the published data on NAD+ side effects comes from this route - and because it's what you'll find discussed in most online forums.
The most frequently reported side effects during intravenous NAD+ infusion are:
Flushing and warmth. A sensation of heat, particularly in the chest, face, and abdomen. This is the single most common side effect and it's directly related to how fast the infusion is running. Slow the drip, and the flushing usually resolves within minutes.
Nausea. Ranges from mild queasiness to genuine discomfort. Again, strongly correlated with infusion rate. Airavaara et al. (2012) in Neurobiology of Disease noted gastrointestinal symptoms as a common transient response during rapid NAD+ administration.
Chest tightness or pressure. This one understandably alarms people, but it's a well-documented vasomotor response - not a cardiac event. It tends to occur when the infusion rate is too high and typically resolves when the rate is reduced. That said, this is precisely the kind of symptom that should be monitored by a healthcare professional, not shrugged off in a lounge chair at a wellness bar.
Headache. Some patients experience mild to moderate headache during or shortly after infusion. This is generally short-lived and may relate to the vasodilatory effects of NAD+ metabolism.
Here's the critical point: the vast majority of these side effects are rate-dependent. They're not signs that NAD+ is doing something harmful. They're signs the infusion is going in too fast for your body to process comfortably.
Why Infusion Rate Matters (And Why Nurse-Administered Isn't Just Marketing)
If there's one takeaway from the NAD+ side effect literature, it's this: slower infusions produce fewer side effects. Full stop.
A 2020 clinical observation report by Grant et al. in Antioxidants found that when intravenous NAD+ was administered over 2–4 hours rather than as a rapid push, the incidence of flushing, nausea, and chest tightness dropped substantially. The therapy didn't change. The speed did.
This is why I take issue with clinics that run NAD+ drips like they're trying to hit a drive-through target time. Your body needs time to metabolise what it's receiving. A trained nurse adjusts the rate based on how you're responding in real time - slowing down if you're flushing, pausing if you're uncomfortable, and ensuring you're never just white-knuckling through side effects because nobody's paying attention.
It's also why any setting where multiple clients receive NAD+ infusions simultaneously with limited individual monitoring raises legitimate concerns. This isn't a vitamin C drip. The infusion rate needs active management.
Less Common Side Effects
Beyond the rate-dependent effects above, there are a handful of less frequently reported responses:
Muscle cramping. Occasionally reported during or after NAD+ infusion. The mechanism isn't fully understood, but it may relate to shifts in electrolyte balance during treatment. Staying well-hydrated before your session helps.
Fatigue after the session. This sounds counterintuitive for a therapy associated with energy, but some people feel genuinely tired in the hours following NAD+ treatment - particularly their first session. Think of it as your cells suddenly having the resources to run repair processes they've been deferring. It typically resolves by the next day.
Bruising or tenderness at the IV site. Standard for any intravenous procedure. Not specific to NAD+ at all - you'd get the same from a saline drip if the cannulation was tricky.
Lightheadedness. Occasionally reported, usually transient, and more common in clients who haven't eaten before their session. I tell my clients: eat something beforehand. Your body's about to do some metabolic heavy lifting.
What the Published Research Says About Safety
Here's where I put on my evidence-based hat and give you the actual data, not the Instagram version.
Braidy et al. (2019) published a comprehensive review in Antioxidants & Redox Signaling examining the role of NAD+ in age-related diseases and its therapeutic potential. Their assessment of NAD+ supplementation across multiple delivery methods found no significant adverse safety signals. They noted that side effects were predominantly mild, transient, and associated with intravenous delivery speed rather than the molecule itself.
Rajman et al. (2018) in Cell Metabolism reviewed the therapeutic potential of NAD-boosting molecules, including direct NAD+ administration. Their findings supported the safety profile, while emphasising the need for more controlled human trials to establish long-term parameters.
Martens et al. (2018) published in Nature Communications a randomised, double-blind, placebo-controlled crossover trial of nicotinamide riboside (an NAD+ precursor) in healthy middle-aged and older adults. Six weeks of supplementation was well-tolerated with no serious adverse events. While this studied an oral precursor rather than direct NAD+, it adds to the broader safety picture of NAD+ pathway supplementation.
Yoshino et al. (2021) in Science studied nicotinamide mononucleotide (NMN) supplementation in prediabetic women and reported it was well-tolerated with no significant adverse effects over 10 weeks.
Conze et al. (2019) published in Scientific Reports a safety assessment of nicotinamide riboside at doses up to 1,000 mg/day for eight weeks and found no clinically significant adverse events.
The pattern across the literature is consistent: NAD+ and its precursors demonstrate a favourable safety profile, with side effects that are mild, predictable, and manageable.
Long-Term Safety: An Honest Assessment
This is where I owe you some intellectual honesty, because the wellness industry isn't great at this part.
Long-term human safety data for direct NAD+ supplementation is still limited. Most published trials run for 6 to 12 weeks. We have robust preclinical data, promising short-term human results, and a molecule that your body naturally produces and relies on - but we don't yet have 5-year or 10-year controlled human studies.
Does that mean NAD+ is dangerous long-term? No. There's no evidence suggesting it is. The molecule is endogenous - your body makes it, needs it, and uses it every day. Restoring levels that have declined with age is, mechanistically, quite different from introducing a foreign compound.
But I won't stand here and tell you we have ironclad 20-year safety data, because we don't. Nobody does. And anyone who claims otherwise is selling you something other than science.
What I can tell you is that the safety signals across all current research are reassuring, the biological rationale is sound, and the risk profile - particularly for subcutaneous delivery at therapeutic doses - is low. That's what the evidence supports today.
Who Should NOT Get NAD+ Therapy
This section isn't optional reading. It's the part I go through with every client before I hand over a pen.
Pregnant or breastfeeding women. There's insufficient safety data for NAD+ supplementation during pregnancy or lactation. Until we have it, the responsible answer is no.
Individuals with active cancer. NAD+ plays a role in cell proliferation pathways, and while the relationship between NAD+ and tumour biology is complex (some research suggests NAD+ may actually support anti-cancer mechanisms), the precautionary principle applies. If you have active cancer, discuss this with your oncologist before considering NAD+ therapy. I won't administer it without their clearance.
People on certain medications. Medications that affect liver metabolism, blood pressure regulation, or cellular energy pathways may interact with NAD+ supplementation. This is why I conduct a full health screening and have blood work reviewed by a doctor before starting any client.
Anyone with a known allergy to NAD+ or its components. Rare, but worth noting.
People who refuse a medical consultation. I'm not being dramatic - I've had people ask me to skip the screening and "just send the pen." The answer is always no. The consultation exists to protect you, and it's a non-negotiable part of the IVgo process.
Why Medical Supervision Matters
I realise this sounds like I'm selling my own service, and I suppose in a way I am - but this point genuinely matters for safety.
NAD+ therapy isn't paracetamol. The dosing, the delivery method, the client's health profile, and the monitoring during treatment all influence both the efficacy and the side effect profile. Here's what proper medical supervision looks like at IVgo:
Pre-treatment screening. Every client undergoes a health history review. Blood work is arranged and reviewed by a doctor. We're looking for contraindications, potential interactions, and baseline health markers before anything goes into your body.
Nurse-administered training. I personally deliver your NAD+ injection pen, demonstrate correct technique, and ensure you're confident with self-administration before I leave. You're not watching a YouTube tutorial and hoping for the best.
Ongoing support. If something feels off during your course - any symptom, any question - you contact me directly. I'm a WhatsApp message away. That's not a chatbot. That's a registered nurse who administered your treatment and knows your health history.
Appropriate referral. If at any point your screening reveals something that warrants further investigation, I refer you to the appropriate medical professional. I'm a nurse, not a GP - I know my scope, and I work within it.
This is the difference between buying a wellness product and receiving a healthcare service. IVgo is the latter.
NAD+ Injection Pen vs. IV Drip: Side Effect Comparison
Since IVgo offers NAD+ as a subcutaneous injection pen rather than an IV drip, this comparison matters for anyone weighing their options.
| Side Effect | IV Drip | Injection Pen (IVgo) |
|---|---|---|
| Flushing/warmth | Common - rate-dependent | Uncommon - slower, steadier absorption |
| Nausea | Moderate frequency - rate-dependent | Rare |
| Chest tightness | Occasional - rate-dependent | Very rare |
| Headache | Occasional | Uncommon |
| Injection site reaction | Bruising from cannulation | Mild redness/tenderness - resolves quickly |
| Fatigue post-treatment | Occasionally reported | Less common - lower peak concentration |
| Duration of side effects | During infusion + hours after | Usually brief, if present at all |
| Medical supervision needed | Yes - continuous during infusion | Initial training session, then self-administered |
| Time commitment | 2–4 hours per session | Seconds per injection, twice weekly |
The fundamental difference comes down to pharmacokinetics. An IV drip delivers NAD+ directly into the bloodstream at a rate controlled by the drip speed - which means high peak concentrations and a correspondingly higher chance of rate-dependent side effects. A subcutaneous injection delivers the same molecule into the tissue beneath the skin, where it absorbs gradually into the bloodstream. Lower peak, smoother curve, fewer systemic side effects.
It's the difference between chugging a bottle of wine and having a glass with dinner. Same substance, very different experience. (I should note that this analogy breaks down if examined too closely - please don't inject wine.)
Frequently Asked Questions
Is NAD+ therapy safe?
Based on current evidence, yes - NAD+ therapy has a favourable safety profile across multiple delivery methods. Side effects are predominantly mild, transient, and rate-dependent (for IV delivery). Long-term data is still accumulating, but no significant safety concerns have been identified in published research to date. The most important safety variable is medical supervision - proper screening, appropriate dosing, and professional oversight.
What does NAD+ flushing feel like?
Flushing during NAD+ IV infusion is typically described as a warm, tingling sensation that starts in the chest or abdomen and can spread to the face and extremities. It's not painful, but it is uncomfortable. Most people compare it to a sudden hot flush. It's directly related to infusion speed and resolves within minutes once the rate is reduced. With subcutaneous injection pens, flushing is uncommon.
Can NAD+ therapy interact with my medication?
Potentially, which is exactly why IVgo requires a health screening and blood work review before starting any client. NAD+ is metabolised through pathways that overlap with certain pharmaceuticals, particularly those affecting liver function and cellular energy metabolism. If you're on chronic medication, disclose everything during your consultation - even supplements.
How is the injection pen different from getting an IV drip?
The pen delivers NAD+ subcutaneously (under the skin) rather than intravenously (into the bloodstream). Absorption is more gradual, peak blood levels are lower, and systemic side effects like flushing and nausea are significantly less common. You self-administer at home after initial nurse training - two quick injections per week instead of a 2–4 hour clinic visit. I cover this in detail in my complete NAD+ guide.
What should I do if I experience side effects from NAD+?
If you're an IVgo client, you contact me directly - call, WhatsApp, or text. I'll assess whether your symptoms are within the expected range or require further attention. For subcutaneous injection pen users, the most common response is mild redness at the injection site, which resolves on its own. If you experience anything unusual - persistent nausea, dizziness, or any symptom that concerns you - reach out immediately rather than powering through. That's what having a nurse on your team is for.
The Bottom Line
NAD+ therapy has side effects. Every honest provider should tell you that. But the evidence - across multiple studies, delivery methods, and patient populations - consistently shows those side effects to be mild, transient, and manageable with proper administration.
The biggest risk factors aren't the molecule itself. They're the delivery speed (for IV), the lack of proper screening (for any method), and the absence of qualified medical supervision. Get those right, and NAD+ therapy sits comfortably in the low-risk category for the vast majority of healthy adults.
What I can't do is promise you zero side effects. What I can do is ensure you're properly screened, competently trained, monitored throughout your course, and supported if anything comes up. That's not a sales pitch - it's the minimum standard of care. At IVgo, it's also the only standard.
If you're considering NAD+ therapy and want to talk through the risks and benefits with someone who'll give you a straight answer, I'm here.
Book your NAD+ consultation:
Call or WhatsApp 074 604 5555 | Visit ivgo.co.za | Instagram: @ivgo_cape_town
Chloé Nefdt is a SANC-registered Professional Nurse and the founder of IVgo, Cape Town's mobile IV therapy, NAD+ and peptide service.
Disclaimer: This article is for informational purposes only and does not constitute medical advice. NAD+ therapy is not a registered medicine in South Africa. Always consult a qualified healthcare professional before starting any new treatment. Individual responses to NAD+ therapy vary - your provider should assess your suitability on a case-by-case basis.