If your Low Dose Naltrexone comes from a compounding
pharmacy and arrives as a liquid, then you’re getting pure
naltexone powder dissolved in distilled water. This is probably
the “purest” way to ingest naltrexone. You don’t need to worry
BUT -- If you get your LDN in any other form, you're
A “filler” is an inert, inactive ingredient that accompanies every
dose of naltrexone you take.
If you make your own LDN --
If you make LDN by crushing ReVia (pronounced REV-yah)
or another commercially manufactured 50mg naltrexone tablet,
you're still injesting filler, because each tablet is comprised of
about 16% Naltrexone and 84% filler.
What kind of filler is in your tablet? This depends on the
manufacturer. Here are the main manufacturers:
Barr Labs – Barr manufactures naltrexone under the brand
name ReVia for the US and Canadian markets. This tablet
contains 50mg naltrexone and these inactive ingredients:
lactose monohydrate, colloidal silicone dioxide, magnesium
stearate, crospovidone, microcrystalline cellulose, purified
water, Opadry beige (coloring). [Information from Barr Labs
Bristol Myers Squibb – BMS manufactures naltrexone under
the brand name ReVia in markets other than the US and
Canada. As of 2002, their 50 mg tablets contain 50 mg of
naltrexone hydrochloride, plus these inactive ingredients (filler):
lactose, microcrystalline cellulose, crospovidone, silicon
dioxide, magnesium stearate, and pale yellow Opadry
(colouring). [Information from a 2002 leaflet by Australian
Prescription Products Guide.]
Mallinckrodt – makes a 50mg naltrexone pill called Depade.
This tablet contains 50mg naltrexone, plus these inactive
ingredients (filler): crospovidone, hydropropyl methylcellulose,
lactose monohydrate, magnesium stearate, microcrystalline
cellulose, polyethelene glycol, polysorbate 80, silicone dioxide,
titanium dioxide, yellow iron oxide, and red iron oxide.
[Information from Mallinckrodt website.]
[Historical Note: The original ReVia was made by Dupont.
The inactive ingredients were: lactose, microcrystalline
cellulose, crospovidone, silicon dioxide, magnesium stearate,
and pale yellow Opadry (colouring). In 2001, Bristol Myers
Squibb acquired DuPont Pharmaceuticals. In April 2002,
BMS sold the ReVia brand-name rights in the US and Canada
to Barr Laboratories. BMS continues to market ReVia outside
of the US and Canada.]
If your LDN is made by a compounding pharmacy –
Ask your pharmacist how it is made.
1. Some compounders make LDN by crushing commercially
manufactured 50mg tablets and putting the powder into
capsules. Because the amount of powder that goes into each
capsule is not enough to fill the capsule, most pharmacies add
additional filler. If this is how you get your LDN, you can find
out which commercially manufactured tablet is being used and
what kind of additional filler is being added.
2. Other compounders don’t crush 50mg tablets; instead, they
use pure naltrexone powder (purchased in bulk from
pharmaceutical companies), which they mix with filler. From
these pharmacists, you can learn what kind of filler you are
Here are some of the most common fillers used by
LACTOSE: Lactose is a naturally-occurring simple
carbohydrate, or sugar, found only in the milk of mammals. For
this reason, it is also commonly referred to as “milk sugar.”
Lactose has long been used as a soluble filler in the manufacture
of orally administered pharmaceuticals. It is safe, stable,
inexpensive, and has a fast dissolution rate. Pharmaceutical-
grade lactose powder is highly pure, and specifically produced
to meet government standards of safety and purity.
Lactose is easily tolerated by most patients. However, if you
are lactose-intolerant (that is, if milk products give you nausea,
diarrhea, abdominal cramping, bloating, or flatulence), you
might want to try another filler.
Note: Dr Bihari asks his patients to use lactose, unless they
have an adverse reaction… not because he believes lactose is
better than other fillers, but because he began his study of LDN
with lactose, and he wants his records to be consistent.
ACIDOPHILOUS – (pronounced Ah-SID-uh-FILL-us) – is
lactic bacteria, or one-celled micro-organisms, used by the
body to promote immunity and proper nutrition. Sold over the
counter as a nutritional supplement and digestive aid,
Acidophilus is sometimes used as a treatment for diarrhea and
constipation. It is commercially available as powder, tablets,
capsules or liquid.
Lactose-intolerant patients sometimes switch to Acidophilus
filler in their LDN capsules.
AVICEL – a brand name for microcrystalline cellulose. Avicel
has been used safely and effectively for 35 years in the food
and pharmaceutical industries. Virtually inert, it is not absorbed
into the system, and will not interfere or interact with other
nutrients, vitamins or minerals. Avicel is made of wood which
has been purified and powdered into extremely tiny particles --
between 0.000039 and 0.0001560 of an inch of pure fiber,
with the consistency of a very fine face powder.
Avicel is the filler used by Skip’s Pharmacy in Boca Raton.
For a fun history of Avicel, “Let Us Have Nothing To Eat,”
CALCIUM CARBONATE – a mineral that occurs naturally
in limestone, marble and coral. Crushed to a fine, flavorless,
odourless powder, it is a natural food additive, and the most
common ingredient in calcium supplements and antacids.
Calcium is absorbed by the small intestine and is used by the
body to build bone tissue. Calcium supplements are generally
well tolerated, but in some patients may cause constipation,
bloating, gas and flatulence.
People with kidney stones, hypercalcemia, sarcoidosis,
hyperparathyroidism, hypervitaminosis D or cancer should not
take calcium carbonate.
People taking calcium supplements are usually advised to take
them with food.
There has been some concern among LDN users that calcium
carbonate is occasionally packed too tight in the capsule, which
can cause a slow-release reaction, rather than the desired fast-
Any questions about filler should be referred to your
doctor or your pharmacist.
-- Last updated 1/7/06
[Note: The information provided on this site is intended for educational and
informational purposes only. Gazorpa.com is not engaged in rendering
medical service or advice, and the information provided is not a substitute for
a professional medical opinion. If you have a medical problem, please contact
a qualified health professional.]