Re: Nardil question for you Nardil vets

Here is a list of the inactive ingredients of the version of Nardil that was marketed in the United States before 2003 (Parke-Davis Division of Pfizer, Inc., 2002):

* mannitol, USP
* povidone, USP
* magnesium stearate, NF
* sucrose, NF
* pharmaceutical glaze, NF (commonly called "shellac")
* carnauba wax, NF
* white wax, NF
* calcium carbonate
* gelatin, NF
* FD&C yellow No. 6
* talc, USP
* acacia, NF
* kaolin, USP
* corn starch, NF
* white wheat flower

Some of the common functions of the above ingredients in pharmaceuticals are described below:

Mannitol: Tablet and capsule dilutent, sweetening agent, tonicity agent, vehicle (bulking agent) for lyophilized preparations (Armstrong, 2003b)

Povidone: Disintegrant, dissolution aid, suspending agent, tablet binder (Kibbe, 2003a)

Sucrose: Tablet-coating agent, base for medical confectionary, granulating agent, suspending agent, sweetening agent, tablet and capsule dilutent, viscosity-increasing agent (Armstrong, 2003c)

Pharmaceutical glaze: Coating agent: used as enteric coating material, is water-insoluble at low pH levels and water-soluble at high pH levels, dissolves slowly in intestinal fluids and other high-pH media, derived from the hardened secretion of the insect Kerria lacca (Pearnchob et al., 2004)

Carnauba wax: Coating agent: used as aqueous emulsion of in powder form to polish sugar-coated tablets, produces tablets of good luster without rubbing, used to produce sustained-release solid-dosage formulations, used to prepare gastro-resistant microspheres (Kobayashi, 2003)

White wax: Polishing agent for sugar-coated tablets, agent used to slow the absorption of an active ingredient from the stomach, agent used to affect the release of an active ingredient from ion-exchange resin beads, stabilizing agent, stiffening agent, controlled-release vehicle (Kibbe, 2003c)

Calcium carbonate: Bulking agent in sugar-coating processes, opacifier in tablet film coating, tablet and capsule dilutent, therapeutic agent (Armstrong, 2003a)

Gelatin: Coating agent, film former, gelling agent, suspending agent, tablet binder, viscosity-increasing agent (Price, 2003)

Talc: Dissolution retardant in controlled-release products, anticaking agent, glidant, tablet and capsule lubricant (Kibbe, 2003b)

Acacia: Tablet binder (can prolong the disintegration times of tablets if used "incautiously"), emulsifying agent, stabilizing agent, suspending agent, viscosity-increasing agent (Shefter, 2003)

Kaolin: Adsorbent, suspending agent, tablet and capsule dilutent (Palmieri, 2003)

Corn starch: Glidant, tablet and capsule dilutent, tablet and capsule disintegrant, tablet binder (Rowley, 2003)

Based on the above information, it does appear that the "old" Nardil had an enteric coating. One of the medication's inactive ingredients -- pharmaceutical glaze, or shellac -- as stated above, is water-insoluble at low pH levels and water-soluble at high pH levels and is consequently used to make enteric coatings. The FDA (2002) has also stated in review document NDA 11-909/SCM-032 that the tablet core of the "old" Nardil was sealed in a coat of pharmaceutical glaze and then coated with sucrose. The extent to which the "old" Nardil's enteric coating made it superior to the film-coated "new" Nardil has been debated. On one hand, one other Psycho-Babble member and I noticed a pronounced reduction in the severity of our symptoms (and I also noticed a reduction in side effects) after switching from film-coated phenelzine to a version of the medication that we prepared by putting the contents of phenelzine tablets into enteric capsules. On the other hand, some members of the Anxiety Community's Nardil forum did not notice a difference after trying this approach. There is also some possible evidence that phenelzine may undergo chemical degradation more rapidly in stomach-like conditions than in small intestine-like conditions, assuming that my reading of Gan-Lin Chen's (1986) doctoral dissertation is correct. This would suggest that a version of phenelzine with an enteric coating would be less likely to be destroyed by the acids in the stomach (before it could be absorbed into the bloodstream and later inhibit the monoamine oxidase enzymes) than a version of the drug without gastro-resistant properties. According to Chen, phenelzine's half-life in a 0.1M hydrochloric acid buffer at pH 1.94 in aerobic conditions is 28.1 h, and the drug's half-life in a phosphate buffer at pH 7.33 in anaerobic conditions is 13,000 h.

Some of those who reject the notion that the "old" Nardil's enteric coating may have contributed to the reported superiority of "old" Nardil over "new" Nardil have argued that it was the "old" Nardil's slower dissolution rate that made it superior. The descriptions of the functions of the inactive ingredients in the "old" Nardil that I listed earlier in this post point to the likelihood that "old" Nardil underwent dissolution more slowly in the body than the "new" Nardil does. As mentioned earlier, talc and acacia are two ingredients from the "old" Nardil that are not in the "new" Nardil that serve to slow the dissolution and disintegration of active pharmaceutical ingredients. So, it does seem likely that the "old" Nardil underwent dissolution and disintegration in the body more slowly than the "new" Nardil does, and this is one difference between the two formulations that may account for the old version's reported superiority. I personally think, based on the results that I saw when I took my Nardil in enteric capsules, that the "old" Nardil's enteric coating was at least a factor in the superiority of the old version of the drug over the new version, but I do think that other factors (such as the "old" Nardil's slower rate of dissolution) may also play a role.

Allen, L.V., & Luner, P.E. (2003). Magnesium stearate. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 354-357). London: Science and Practice.

Armstrong, N.A. (2003a). Calcium carbonate. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 68-71). London: Science and Practice.

Armstrong, N.A. (2003b). Mannitol. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 373-377). London: Science and Practice.

Armstrong, N.A. (2003c). Sucrose. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 622-625). London: Science and Practice.

Chen, G.-L. (1986). The chemical kinetics of phenelzine degradation. Unpublished doctoral dissertation, University of Iowa, Iowa City.

FD&C Yellow No. 6. (2006). Code of Federal Regulations, Title 21, Section 74.1706. Retrieved March 9, 2006, from LexisNexis Academic database.

Kibbe, A.H. (2003a). Povidone. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 508-513). London: Science and Practice.

Kibbe, A.H. (2003b). Talc. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 641-643). London: Science and Practice.

Kibbe, A.H. (2003c). Wax, white. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 687-688). London: Science and Practice.

Kobayashi, N.H. (2003). Wax, carnauba. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 679-680). London: Science and Practice.

Palmieri, A. (2003). Kaolin. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 316-318). London: Science and Practice.

Parke-Davis Division of Pfizer, Inc. (2002). Nardil(R) (Phenelzine sulfate tablets, USP), labeling information. Retrieved January 13, 2006, from the U.S. Food and Drug Administration's Web site: http://www.fda.gov/cder/foi/label/2002/11909slr030lbl.pdf

Pearnchob, N., Dashevsky, A., & Bodmeier, R. (2004). Improvement in the disintegration of shellac-coated soft gelatin capsules in simulated intestinal fluid. Journal of Controlled Release, 94, 313-321. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/14744483

Price, J.C. (2003). Gelatin. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 252-254). London: Science and Practice.

Rowley, G. (2003). Starch. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 603-608). London: Science and Practice.

Shefter, E. (2003). Acacia. In R.C. Rowe, P.J. Sheskey, & P.J. Weller (Eds.), Handbook of pharmaceutical excipients (pp. 1-2). London: Science and Practice.

U.S. Food and Drug Administration. (2002). Office of Clinical Pharmacology and Biopharmaceutics review (NDA 11-909/SCM-032). City of publication not available: Author.

Dx: schizoaffective disorder

Treatments: Abilify & vitamin D3

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