Testosterone is an essential hormone for the muscle building process. It promotest protein synthesis and the growth of protein tissues with receptors. Its anabolic effects in building more bone and muscle mass allows testosterone to play a vital role in the growth of muscle mass and increased strength.

All together, testosterone plays a pivotal role for muscle tropism in which this hormone will play and important role in replenishing muscle tissue and fiber broken down during workouts. Hence, testosterone is vital for those looking to increase muscle mass, strength, and to improve muscle tone and definition.

With higher levels of testosterone, you’ll be ready to dominate your workout! Higher testosterone levels help promote protein synthesis and muscle growth, higher metabolism, increased bone density and strength, and may have a positive effect on your sexual well-being!

3,120mg D-Aspartic Acid: In a recent clinical trial, subjects who took D-Aspartic Acid increased their testosterone serum levels by an average of 42% in just 12 days. Their luteinizing hormone (LH) levels also increased. By contrast, the placebo group only saw a 2.1% increase in testosterone. Subjects took 3,120mg of D-Aspartic Acid a day - the exact amount in each daily dose of Syntheroid.

D-Aspartic Acid is non-functional amino acid produced naturally in your body. It’s primarily found in the “hotspots” of hormone production - the testes, pituitary gland and hypothalamus.

d-aspartic acid graph

300mg Tribulus Terrestris (40% saponins): A potent, all-natural compound that delivers statistically significant increases in testosterone levels, as well as increasing dihydrotestosterone and dehydroepiandrosterone. It has been shown to improve aphrodisiac activity. Tribulus terrestris is a non-hormonal herb that has been used for hundreds of years to restore and improve libido in men.

Terrestris works with the body to stimulate the production of testosterone and boosts sexual performance. But, more importantly, Tribulus Terrestris helps improve athletic performance. Since this ingredient not in itself is not a hormone, Tribulus Terrestris works to maximize your muscle and gain strength.

300mg Horny Goat Weed (10 Icariin): Also known as epimedium, this powerful sexual enhancer has been shown to improve sexual desire and function in men. Discovered by a Chinese goat herder who found goats who ate this herb to have increased sexual activity, this amazing ingredient has been shown to promote nitric oxide levels in the bloodstream. Horny goat weed promotes greater energy and relaxes smooth muscle simultaneously!

200mg Maca Root: Maca , AKA the “Peruvian SuperFood”, is a root cultivated high the Andes mountains. It’s rich in phytonutrients, amino acids, vitamins and fatty acids. We included it in Syntheroid because it contains sterols that not only boost testosterone levels, but may also blunt the body’s production of estrogen.

200mg Mucuna Pruriens: Mucuna has been used for years to increase muscle mass and boost libido. It works by encouraging the endogenous production of testosterone and human growth hormone. It is a muscle-boosting staple you shouldn’t go without.

200mg Eurycoma Longifolia 20:1: This powerful extract is also known as LongJack and increases IGF1 levels. It is well-known for its ability to improve athletic performance, boost testosterone levels, and inhibit SHBG. Eurycoma longifolia also allows more free testosterone to remain in the bloodstream without increasing estrogen levels, making it the perfect testosterone booster. Eurycoma longifolia also enhances muscle strength and tone, and boosts immune system functions. The bonus is that Eurycoma can reduce body fat levels, fight fatigue, and prevent physical exhaustion.

10mg Boron (Boron AAC): Boron is the forgotten nutrient. In reality, it’s a important trace mineral that’s essential for bone health. In a 2011 clinical study, boron was found to increase free testosterone, decrease SHBG, and decrease estradiol levels in just 7 days.

10mg Bioperine: This patented ingredient is the glue that holds this amazing formula together. It has been proven to improve nutrient absorption and also increases the effectiveness of digestion. It does this safely and makes the intestinal wall more permeable. This acts to increase absorption levels leading to improve the effectiveness of the supportive nutrients that are taken in.


"Syntheroid is the most powerful stack I have taken ever. I was 220 when I started by the end of my cycle I was weighing in at 235. It totally sped my metabolism up to give me an amazingly cut ripped look I wanted. Truth is this product spntheroid works like no other testo booster out there!"

Jeff S.


"XPI Syntheroid is by far the best testosterone booster I ever tried. I am a trainer and have been looking for the perfect product to help my clients achieve their goals. I've been disappointed by all the other products out there. No better way to show others that it works by trying it yourself. Well, I noticed big gains in power and the strength. It really helps you get the edge at the gym. For me, I really wanted to get definition and cut out the excess fat, try to get in performance shape. Syntheroid delivered! From me and all my clients, THANKS for this AMAZING product!!!"

Presley Okobia


"Syntheroid is the most jam up stack I have taken ever. I was about 6'3" 220 when I started by the end of my cycle I was 6'3" 247 solid except for a ll bit on my stomach but u know how that is. It also sped my metabolism up to give me the cut look I wanted. Truth is this product syntheroid works like it or not."

Tyler W.


"I started taking Syntheroid at the beginning of 2008. I do hard lift but I was only able to lift for a good hour. I have seen an amazing boost on my maxes. My bench on max before was 225, in a matter of 1 month using 1 bottle and lifting my max jumped up to 255. I also experienced major jump in my squat. Before our Christmas break my max squat was 365. But as soon as I started taking Syntheroid I could see how fast my squat was increasing. By the end of my first bottle of Syntheroid my max went from 365 up to 395. In the time since I have started taking Syntheroid I have gained 5 pounds of muscle. As soon as you start taking Syntheroid you will notice a change and an energy boost. I have had no side effects at all! It worked amazing for me and I recommend it to anybody trying to become stronger or bigger. I will continue using this product. It is worth every penny!"

Trevor H.


"Iam 43 years old, and according to my doctor, I am make his job of taking care of my very easy. The results in the photo are only from about 2 months of using the product. I can't wait to see what I will look like after 6 months of using Syntheroid. I am impressed at my results and I would recommend Syntheroid to any with a similar body size as me. I am 5 foot 5 inches, and 165 pounds, but before taking Syntheroid, I was 177 pounds."

Lem M.


"after 2 weeks of use I'm more defined harder and more energy"

Nicholas M.

Syntheroid is guaranteed to deliver results! If for ANY reason you are not satisfied, simply contact customer support for instructions on how to return your order of the one bottle you tried and any others in unused and resalable condition for your money back (minus S&H). With a guarantee like this you have virtually nothing to lose. Try Syntheroid today!

Q: When can I expect results with SYNTHEROID?

A: Most users find improved energy and strength during the first 3 days of using SYNTHEROID. Muscle growth and increases in muscle mass will vary depending upon workout intensity and schedules. Individual results will vary, but some see results within the first week while others may take longer to see results.

Q: Will SYNTHEROID cause me to test positive for steroids?

A: SYNTHEROID is not a steroid or prohormone. In fact, SYNTHEROID is created with only safe, all-natural ingredients that will naturally increase your body’s ability to create more testosterone. It does not work with synthetic hormones in any way and will not cause a positive test result for steroids. Before taking SYNTHEROID, we recommend that you consult a physician to see if it is right for you.

Q: How Much is SYNTHEROID?

A: SYNTHEROID normally retails for $95.50, but through this limited introductory offer you can buy SYNTHEROID for just $59.95. That’s 40% off the retail price!

Q: Do I have to exercise and diet to see results?

A: SYNTHEROID works best when it is used in conjunction with a healthy diet and regular exercise. Although SYNTHEROID can help you boost your testosterone levels and cause great results by itself, the best way to get maximum results is by also maximizing your diet and exercise activity.

Q: How quickly will I get my order?

A: To ensure prompt delivery, we ship each order within one business day. Domestic orders are shipped via FedEx Home Delivery (1-5 days), FedEx 2 Day Air, FedEx Standard Overinight, USPS First Class (2-5 days) and USPS Priority (2-3 days). International orders are shipped via FedEx International Mail (10-14 days) and FedEx International Priority (3-5 days, highly recommended).

Q: How does the money back guarantee work?

A: You can receive a full refund for one used bottle and any other bottles in resalable condition less shipping costs. Please contact customer support within 90 days from your purchase date to receive complete instructions for returns.

syntheroid testosterone booster bonus Secratatropin