Laurabolin® (nandrolone laurate)
Nandrolone laurate is an injectable form of the anabolic steroid nandrolone. The laurate ester applied here is two carbon atoms longer than decanoate, and consequently this agent forms a slightly longer-lasting drug deposit around the area of injection than Deca-Durabolin. Given its strong delayed-release properties, it is possible to administer nandrolone laurate once every three to four weeks in a medical setting. As a nandrolone injectable, this drug provides a moderately strong anabolic effect, which is accompanied by a low level of estrogenic and androgenic properties. Although not widely used, nandrolone laurate is favored by athletes and bodybuilders for its ability to promote slow steady gains in lean mass with minimal side effects.
Nandrolone laurate was developed during the 1960’s, a time when many new nandrolone esters were being synthesized and investigated. This long-acting ester of nandrolone is usually identified as a veterinary drug, but was actually prescribed to humans before it was adopted for animal use. The only brand name of reference is Clinibolin, which was sold for a brief time on the German drug market around the end of the 1960’s. Nandrolone laurate was ultimately short-lived as a human medication, however, and from this point on would be used exclusively in veterinary preparations. There is nothing particular that makes the drug poorly suited for human use, and its discontinuance probably had much more to do with the dominance of Organon’s Deca-Durabolin, which made nandrolone laurate fairly superfluous as a prescription drug, than any faults of the drug itself.
As a veterinary drug, nandrolone laurate is most commonly identified with the Laurabolin brand name. Laurabolin is manufactured by Intervet, and is found in a variety of countries including Mexico, Chile, The Netherlands, Australia, and Colombia.
It is used with cats, dogs, horses, pigs and cattle, typically to offset malnutrition caused by viral or parasitic illness, to treat anemia, counter the catabolic effects of corticosteroids, and to improve the overall physical condition of highly active or elderly animals. The Laurabolin brand has also been sold at one time by Werfft-Chemie in Austria and Vemie in Germany, however these products have since been discontinued. In addition to the Laurabolin brand name, the drug had also been marketed in the past under the trade names Fortadex (Hydro, Germany), Fortabol (Parfam, Mexico), and Lauradrol 250 (Loeffler, Mexico). Today, only the Intervet products are known to exist.
Nandrolone laurate is available in select veterinary drug markets. Composition and dosage may vary by country and manufacturer, but usually contain 20 mg/mL or 50 mg/mL of steroid dissolved in oil.
Nandrolone laurate is a modified form of nandrolone, where a carboxylic acid ester (lauric acid) has been attached to the 17-beta hydroxyl group. Esterified steroids are less polar than free steroids, and are absorbed more slowly from the area of injection. Once in the bloodstream, the ester is removed to yield free (active) nandrolone. Esterified steroids are designed to prolong the window of therapeutic effect following administration, allowing for a less frequent injection schedule compared to injections of free (unesterified) steroid. Nandrolone laurate is designed to provide a slow release of nandrolone for up to 3 to 4 weeks following injection.
Side Effects (Estrogenic):
Nandrolone has a low tendency for estrogen conversion, estimated to be only about 20% of that seen with testosterone.1
This is because while the liver can convert nandrolone to estradiol, in other more active sites of steroid aromatization such as adipose tissue nandrolone is far less open to this process.2 Consequently, estrogen-related side effects are a much lower concern with this drug than with testosterone. Elevated estrogen levels may still be noticed with higher dosing, however, and may cause side effects such as increased water retention, body fat gain, and gynecomastia. An anti-estrogen such as clomiphene citrate or tamoxifen citrate may be necessary to prevent estrogenic side effects if they occur. One may alternately use an aromatase inhibitor like Arimidex® (anastrozole), which more efficiently controls estrogen by preventing its synthesis. Aromatase inhibitors can be quite expensive in comparison to anti-estrogens, however, and may also have negative effects on blood lipids.
It is of note that nandrolone has some activity as a progestin in the body.3 Although progesterone is a C-19 steroid, removal of this group as in 19-norprogesterone creates a hormone with greater binding affinity for its corresponding receptor. Sharing this trait, many 19-nor anabolic steroids are shown to have some affinity for the progesterone receptor as well.4 The side effects associated with progesterone are similar to those of estrogen, including negative feedback inhibition of testosterone production and enhanced rate of fat storage. Progestins also augment the stimulatory effect of estrogens on mammary tissue growth. There appears to be a strong synergy between these two hormones here, such that gynecomastia might even occur with the help of progestins, without excessive estrogen levels. The use of an antiestrogen, which inhibits the estrogenic component of this disorder, is often sufficient to mitigate gynecomastia caused by nandrolone.
Side Effects (Androgenic):
Although classified as an anabolic steroid, androgenic side effects are still possible with this substance, especially with higher doses. This may include bouts of oily skin, acne, and body/facial hair growth. Anabolic/androgenic steroids may also aggravate male pattern hair loss. Women are warned of the potential virilizing effects of anabolic/androgenic steroids. These may include a deepening of the voice, menstrual irregularities, changes in skin texture, facial hair growth, and clitoral enlargement. Nandrolone is a steroid with relatively low androgenic activity relative to its tissue-building actions, making the threshold for strong androgenic side effects comparably higher than with more androgenic agents such as testosterone, methandrostenolone, or fluoxymesterone. It is also important to point out that due to its mild androgenic nature and ability to suppress endogenous testosterone, nandrolone is prone to interfering with libido in males when used without another androgen.
Note that in androgen-responsive target tissues such as the skin, scalp, and prostate, the relative androgenicity of nandrolone is reduced by its reduction to dihydronandrolone (DHN).5 6 The 5-alpha reductase enzyme is responsible for this metabolism of nandrolone. The concurrent use of a 5-alpha reductase inhibitor such as finasteride or dutasteride will interfere with site-specific reduction of nandrolone action, considerably increasing the tendency of nandrolone to produce androgenic side effects. Reductase inhibitors should be avoided with nandrolone if low androgenicity is desired.
Side Effects (Hepatotoxicity):
Nandrolone is not c-17 alpha alkylated, and not known to have hepatotoxic effects. Liver toxicity is unlikely.
Side Effects (Cardiovascular):
Anabolic/androgenic steroids can have deleterious effects on serum cholesterol. This includes a tendency to reduce HDL (good) cholesterol values and increase LDL (bad) cholesterol values, which may shift the HDL to LDL balance in a direction that favors greater risk of arteriosclerosis. The relative impact of an anabolic/androgenic steroid on serum lipids is dependant on the dose, route of administration (oral vs. injectable), type of steroid (aromatizable or nonaromatizable), and level of resistance to hepatic metabolism. Studies administering 600 mg of nandrolone decanoate per week for 10 weeks demonstrated a 26% reduction in HDL cholesterol levels.7 This suppression is slightly greater than that reported with an equal dose of testosterone enanthate, and is in agreement with earlier studies showing a slightly stronger negative impact on HDL/LDL ratio with nandrolone decanoate as compared to testosterone cypionate.8 Nandrolone injectables, however, should still have a significantly weaker impact on serum lipids than c-17 alpha alkylated agents. Anabolic/androgenic steroids may also adversely affect blood pressure and triglycerides, reduce endothelial relaxation, and support left ventricular hypertrophy, all potentially increasing the risk of cardiovascular disease and myocardial infarction.
To help reduce cardiovascular strain it is advised to maintain an active cardiovascular exercise program and minimize the intake of saturated fats, cholesterol, and simple carbohydrates at all times during active AAS administration. Supplementing with fish oils (4 grams per day) and a natural cholesterol/antioxidant formula such as Lipid Stabil or a product with comparable ingredients is also recommended.
Side Effects (Testosterone Suppression):
All anabolic/androgenic steroids when taken in doses sufficient to promote muscle gain are expected to suppress endogenous testosterone production. For sake of comparison, studies administering 100 mg per week of nandrolone decanoate for 6 weeks have demonstrated an approximate 57% reduction in serum testosterone levels during therapy. At a dosage of 300 mg per week, this reduction reached 70%.9 It is believed that the progestational activity of nandrolone notably contributes to the suppression of testosterone synthesis during therapy, which can be marked in spite of a low tendency for estrogen conversion.10 Without the intervention of testosterone-stimulating substances, testosterone levels should return to normal within 2-6 months of drug secession. Note that prolonged hypogonadotrophic hypogonadism can develop secondary to steroid abuse, necessitating medical intervention.
The above side effects are not inclusive. For more detailed discussion of potential side effects, see the Steroid Side Effects section of this book.
Nandrolone laurate is not approved for use in humans. Prescribing guidelines are unavailable. When used for physique- or performance- enhancing purposes, a dose of 200-400 mg given every 7-10 days is most common, taken in cycles 8 to 12 weeks in length. This level is sufficient for most users to notice measurable gains in lean muscle mass and strength, which should be accompanied by a low level of estrogenic and androgenic activity. Higher doses (450-600 mg every 7-10 days) will impart a stronger anabolic effect, but can be difficult given the relatively low concentration this steroid is usually found in. Instead, many opt to combine this agent with other anabolic/androgenic steroids. Given its properties, it seems to fit well for both bulking and cutting purposes, and can reasonably replace Deca-Durabolin in cycles.
Nandrolone laurate is not approved for use in humans. Prescribing guidelines are unavailable. When used for physique- or performance- enhancing purposes, a dosage of 100 mg every 1014 days is most common, taken for 4 to 6 weeks. Although only slightly androgenic, women are occasionally confronted with virilization symptoms when taking this compound. Should virilizing side effects become a concern, the drug should be discontinued immediately to help prevent their permanent appearance. After a sufficient period of withdrawal, the shorter-acting nandrolone Durabolin® might be considered a safer (more controllable) option. This drug stays active for only several days, greatly reducing the withdrawal time if indicated.
Pharmaceutical preparations containing nandrolone laurate remain scarce. In reviewing some of the remaining products and changes in the global pharmaceutical market, we have made the following observations.
The Intervet brand name Laurabolin product is almost exclusively associated with this compound. It remains available in select markets of Europe and the America’s, and is not widely diverted for black market sale.
1 Biosynthesis of Estrogens, Gual C, Morato T, Hayano M, Gut M and Dorfman R. Endocrinology 71 (1962):920-25.
2 Aromatization of androstenedione and 19-nortestosterone in human placental, liver and adipose tissues (abstract). Nippon Naibunpi Gakkai Zasshi 62:18-25,1986.
3 Competitive progesterone antagonists: receptor binding and biologic activity of testosterone and 19-nortestosterone derivatives. Reel JR, Humphrey RR, Shih YH, Windsor BL, Sakowski R, Creger PL, Edgren RA. Fertil Steril 1979 May;31(5):552-61.
4 Studies of the biological activity of certain 19-nor steroids in female animals. Pincus G, Chang M, Zarrow M, Hafez E, Merrill A. December 1956.
5 Different pattern of metabolism determine the relative anabolic activity of 19-norandrogens. J Steroid Biochem Mol Bio 53:255-7,1995.
6 Relative binding affinities of testosterone, 19-nortestosterone and their 5alpha reduced derivatives to the androgen receptor and to other androgenbinding proteins: A suggested role of 5alpha-reductive steroid metabolism in the dissociation of ‘myotropic’ and ‘androgenic’ activities of 19nortestosterone. Toth M, Zakar T. J Steroid Biochem 17 (1982):65360.
7 Metabolic effects of nandrolone decanoate and resistance training in men with HIV. Sattler FR, Schroeder ET, Dube MP, Jaque SV, Martinez C, Blanche PJ, Azen S, Krauss RM. Am J Physiol Endocrinol Metab. 2002 Dec;283(6):E1214-22. Epub 2002 Aug 27.
8 Lipemic and lipoproteinemic effects of natural and synthetic androgens in humans. Crist DM, Peake GT, Stackpole PJ. Clin Exp Pharmacol Physiol 1986 Jul;13(7):513-8.
9 The administration of pharmacological doses of testosterone or 19nortestosterone to normal men is not associated with increased insulin secretion or impaired glucose tolerance. Karl E. Friedl et al. J Clin Endocrinol Metab 68:971, 1989.
10 Influence of nandrolonedecanoate on the pituitary-gonadal axis in males. Bijlsma J, Duursma S, Thijssen J, Huber O. Acta Endocrinol 101 (1982):10812.