NAD+ Side Effects

NAD+ injections and nasal spray are prescription treatments, and every provider on this site routes you through a clinician review before dispensing. That review exists to catch the things a website cannot: your medical history, the medications you already take, and whether this treatment is appropriate for you at all. Nothing on this page replaces it.

What follows is a summary of the reactions people commonly report, drawn from what providers themselves publish. It is background for a conversation with your clinician, not a substitute for one.

Commonly reported side effects

• Flushing or warmth. A brief sensation of heat, most often described around the time of administration.
• Nausea. Usually reported in the first days of treatment and usually described as mild.
• Headache. Common during the initial adjustment period.
• Fatigue. Some people report feeling more tired, not less, in the first few days before that reverses.
• Injection-site reaction. With injections specifically: redness, mild swelling or tenderness where the shot was given.
• Nasal irritation. With nasal spray specifically: brief stinging or irritation after use.

How long they usually last

The pattern people describe most often is front-loaded: whatever they notice, they notice in week one, and it fades as they continue. Injection-site reactions typically settle within a day. Systemic effects such as flushing, nausea or headache are usually described as easing across the first one to two weeks.

That pattern is common, not guaranteed. If something is not improving on that timeline, that is the point to message your provider rather than push through it.

When to contact your provider

• Any reaction that is severe rather than mild.
• Anything still present beyond the first couple of weeks.
• Signs of an allergic reaction, rash, swelling, difficulty breathing. Seek urgent medical care first.
• Starting any new medication while on NAD+ treatment.
• An injection site that becomes increasingly painful, hot or swollen rather than settling.

This is one of the practical arguments for choosing a provider with included messaging. He & She MD publishes unlimited provider messaging and ReadyRx publishes ongoing care and support from its clinical team; Enhanced.com includes ongoing monitoring by board-certified providers; DirectMeds publishes 1:1 medical support. When something feels off in week one, that access is what you are actually paying for.

What to tell your provider at intake

The intake questionnaire is the safety step. Answer it completely, existing conditions, every current medication and supplement, allergies, and whether you are pregnant or breastfeeding. The clinician's decision, and your protocol, are built on those answers, and an incomplete intake undermines both.

Providers with strong support and refund terms

If side effects are your main concern, weight two things when choosing: how easily you can reach a clinician, and how easily you can stop. Enhanced.com publishes a 90-day money-back guarantee with no questions asked, the strongest terms we track. Embody and Sprout Health both state you can cancel anytime.

Pricing and plan terms last verified August 2026. Provider terms change often, always confirm the current price, renewal rate and cancellation policy on the provider's own site before enrolling. We may earn a commission from partner links on this page, which never affects our rankings - see our disclosure. This page is informational and is not medical advice.