It is generally recommended to start with a low niacin dosage and increase it gradually (known as titration). Titration schedules will vary depending on the specific niacin product, how you respond to the vitamin, and what condition is being treated. When switching from one product to another, it is recommended to start back at a low niacin dose and gradually increase the dosage.
The dose of niacin (brand names include Niacor®, Niaspan®, Slo-Niacin®, and several others) that your healthcare provider recommends will vary, depending on a number of factors, including:
- The medical condition being treated
- How you react to niacin
- Other medications you are taking
- Other medical conditions you may have.
As is always the case, do not adjust your dosage unless your healthcare provider specifically instructs you to do so.
The dietary recommended allowances (RDAs) for niacin are actually fairly low, ranging from 2 mg a day for infants up to 18 mg a day for breastfeeding women. Most people get enough niacin through their diets to prevent pellagra (a niacin deficiency disease).
The niacin dose for treating pellagra ranges from 100 to 500 mg total per day.
If you happen to start taking niacin at the full recommended dose for improving cholesterol, you probably won't stay on it very long, due to intolerable side effects, particularly the niacin flush. Instead, it is best to start with a low dose and increase it slowly. This is known as titration. Sample titrations schedules for IR, SR, and ER niacin are as follows:
- IR (immediate-release) niacin, such as Niacor and various non-prescription products:
- Week 1 -- 100 mg three times daily
- Week 2 -- 200 mg three times daily
- Week 3 -- 350 mg three times daily
- Weeks 4 through 7 -- 500 mg three times daily
- Weeks 8 through 11 -- 750 mg three times daily
- Week 12 and beyond -- 1000 mg three times daily
- ER (extended-release) niacin, available as prescription-only Niaspan:
- Weeks 1 through 4 -- 500 mg once daily at bedtime
- Weeks 5 through 8 -- 1000 mg once daily at bedtime
- Weeks 8 and beyond -- 1500 mg once daily at bedtime, increasing to 2000 mg at bedtime if necessary
- SR (sustained-release, slow-release, timed-release, and controlled release), available as Slo-Niacin and various other non-prescription products:
- Week 1 -- 250 mg twice daily
- Weeks 2 through 5 -- 500 mg twice daily
- Weeks 6 through 9 -- 750 mg twice daily
- Weeks 10 and beyond -- 1000 mg twice daily.
You may notice that the labels for non-prescription niacin products (especially SR niacin) recommend much lower, once-daily doses. This is because these products are nutritional supplements (not FDA-approved medications). Many healthcare providers do not recommend non-prescription niacin SR products, due to an apparently higher risk for liver damage (see Types of Niacin for more information).
When switching from one form of niacin to another, it is recommended to start back at a low dose and gradually increase the dosage, just as if you had never taken niacin before.