Purchase in USA

Purchase in USA of vitamins B3 and C in mega sizes and of sustained release

With sustained release or time release ie. slow release is generally required only half the dose.

Niacin (nikotinsyre).
Niacin can cause the tingling of the skin (flush) and redness as histamine is released and the capillaries expand. The effect is reduced by the use of slow release niacin, and also by frequent use, so that the histamine stores do not become large. Since niacin provides a more effective sleep, it is a good idea to ingest just before bedtime. The flush can be moderated by aspirin (one tablet before each dose of niacin) for a few days, antihistamines (eg, vitamin C) or sedatives. If niacin cannot be tolerated, “inositol niacinate” is another and slightly weaker version of vitamin B3 an option.
https://dk.iherb.com/pr/Now-Foods-Niacin-500-mg-250-Tablets/693
Now Foods, Niacin, 500 mg, 250 Tablets 
Go complete down!!! for all delivery options.

Niacinamid. Dose as niacin. These tablets are 3 times larger than the others. Used by Dr. Kaufman for Arthritis. Not for Cholesterol Control and Raynaud’s disease.
https://dk.iherb.com/pr/Source-Naturals-Niacinamide-B-3-Timed-Release-1-500-mg-100-Tablets/1348
Source Naturals, Niacinamide, B-3, Timed Release, 1,500 mg, 100 Tablets 
Go complete down!!! for all delivery options.

Inositol Hexanicotinate. Dose as niacin. Not for Raynaud’s disease.
https://dk.iherb.com/pr/Natrol-Niacin-Time-Release-500-mg-100-Tablets/15932
Natrol, Niacin, Time Release, 500 mg, 100 Tablets
Go complete down!!! for all delivery options.

C-vitamin. The beneficial sustained release version with Rose Hips.
https://dk.iherb.com/pr/Now-Foods-C-1000-250-Tablets/466
Now Foods, Vitamin C, 1000 mg, 250 Tablets. 
Go complete down!!! for all delivery options.
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