
Tarsul combines cream of tartar, a natural source of potassium, with MSM, a sulfur compound found in many foods. Two ingredients, no proprietary blend, made in San Diego since 2010.

Many adults get less potassium than recommended, mostly because they eat fewer fruits, vegetables, and beans than they should. Food is the best place to close that gap. A supplement can help fill part of it, but it is not a replacement for a healthy diet.
Good food sources of potassium include:

Tarsul is a simple supplement made from two ingredients: potassium bitartrate (cream of tartar) and MSM (methylsulfonylmethane). There are no fillers or proprietary blends, so you always know what you are taking.
Two ingredients, no proprietary blend
Made in San Diego, USA 🇺🇸
Capsules or powder
A source of dietary potassium
Adds MSM, a sulfur compound


Cream of Tartar
Potassium Bitartrate
A natural byproduct of winemaking, purified into a fine white powder. The FDA lists it as a food ingredient that is generally recognized as safe, and it is a concentrated source of potassium.

MSM Sulfur
Methylsulfonylmethane
A sulfur compound found in small amounts in many foods. It is widely used in supplements and is generally described as well tolerated.
Common questions about what is in Tarsul and how to take it safely.
Two ingredients: cream of tartar (potassium bitartrate) and MSM (methylsulfonylmethane). There is no proprietary blend.
Follow the label on your bottle and start at the low end of the suggested range. Our dosage and ingredients guide explains how to measure it.
Because cream of tartar is high in potassium, talk with your doctor before using Tarsul if you have kidney problems or take medicines that raise potassium, such as ACE inhibitors, ARBs, or potassium-sparing water pills.
No. Tarsul is a dietary supplement, not a medicine, and it is not intended to diagnose, treat, cure, or prevent any disease. Do not stop or change any prescription without talking to your doctor.
No. Taking large amounts of cream of tartar at once can raise blood potassium to dangerous levels. Stay within the label directions.
Read about cream of tartar and MSM on tarsul.com, or contact us at [email protected] or 619-500-4403.
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