A diet product’s worth depends on whether it helps people lose weight. Let’s find out if Synedrex works. We needed to learn as much as possible about the ingredients, side effects, and clinical support. We also took a long, hard look at customer experiences. We broke it all down and condensed it to give you the info you need.
What is Synedrex?
First off, Synedrex is a thermogenic supplement  supposedly helping to boost metabolism and burn fat. The ingredients are methylxanthine, methylpentane citrate, sulbutiamine, sandalwood extract, yohimbine, alpha lipoic acid, and poly-thyronine. The company recommends not taking more than two capsules per day. The small container means there’s no trouble taking them on the go. 
The company behind Synedrex, Metabolic Nutrition, started the business online in 1997. Trusted retailers and the official website sell the supplement. We like that the ingredients are available for the dieter and that we found some positive comments, but read on…
Synedrex Side Effects – “Do You Need to Worry?”
The first negative we found was with Synedrex side effects, which could be associated with methylxanthine.  “No dieter wants to feel shaky and jittery after taking a product,” says our Research Editor. “You can have increased energy and metabolism without the problems.”
As one dieter puts it, “The side effects while on it included excessive sweating, jitters and insomnia.”
Another user reports, even more, Synedrex side effects, ”It gave good energy, but it was too much. It made my heart feel racy.”
During our research, we did stumble on a few dieters who didn’t have the same problem. One said, “The first day I started I got incredibly hot and enough energy to last a week, had a little trouble sleeping but by day 2 that pretty much went away.” 
A customer shared, “I haven’t had any of the side effects listed in any of these reviews.”
Ineffective – “Frequent Complaint”
Probably one of the biggest issues with a weight-loss supplement like this is effectiveness. Clinically speaking, there are some energy boosters in there that could increase metabolism enough to affect calorie burn, but no two dieters will react the same. According to some, Synedrex ingredients do nothing to help you lose. “I didn’t lose any weight. I will look for a better fat burner,” a user reports. 
Another dieter with the same problem says, ”There was no change in my weight at all.”
We did read some supportive comments along the way. As one user said, “Keeps me going. Makes me sweat.”
Another commented, “I only take one pill per day, in the morning and feel it helps sustain my energy all day.”
You only need one negative, like an adverse reaction, to ruin your chance of long-term weight-loss success. In the case of Synedrex, if the side effects are as harsh as dieters report, not matter if quality research doesn’t report such issues in most participants, that’s a bad sign.
The Science – “Is There Proof?”
We visited the Science Center portion of the Metabolic Nutrition website to see if there was any support for the weight-loss product. We found articles about supplements and exercise, but no research. The most important parts are caffeine and yohimbine,  two stimulants. We know these ingredients boost energy and promote a stronger metabolism, but too much can do more harm than good. Based on the side effects there may be too much in . At DietSpotlight, we need to see facts to support claims. If there’s none out there, or if the formula may cause issues, that’s not a good sign.Also: read our Leptigen Weight-Loss Kit review »
The Bottom Line – Does Synedrex Work?
So, will Synedrex help you lose weight? The business has been around for 20 years, and some dieters do report positive results, but we feel uncomfortable giving our support because of the lack of clinical support. Plus, it bothers us that dieters reported side effects and lack of results.
If the time has come to shed off the extra weight, our suggestion is to find a supplement that contains clinically supported ingredients, with no known side effects offered at a price you can afford.
Among the best products we’ve found this year is one called Leptigen. The proprietary blend is a combination of ingredients shown in published scientific research to spur metabolism and boost fat loss. Dieter’s aren’t talking about negative side effects, and users report seeing great results.
Also, the company that makes Leptigen is so confident in the formula they’re offering a Special Trial Offer, which we like.
Previous Synedrex Review (Updated July 9, 2014):
Synedrex - What You Should KnowSynedrex is a pill form diet supplement that is advertised to help dieters shed fat and water weight by controlling food cravings. This diet pill is also supposed to give dieters an endless supply of energy, block carbohydrates and help to curb food cravings similar to GNC Burn 60. Synedrex is manufactured and marketed by the company Metabolic Nutrition. The company unfortunately has an unpleasing BBB rating. Looking at the ingredients one can see that there are some fat burners on the list; both green tea and garcinia cambogia are well known fat burners that have been shown in some studies to produce results. There does seem to be some disparity among websites that claim this product does not work as well due to insufficient amounts of these fat burners.
List of Ingredients of SynedrexChromium, caffeine anhydrous, green tea extract, garcinia cambogia, l-tyrosine, l-carnitine, HPMC, cocoa extract, 5-HTP, and jojoba bean.
Product FeaturesSynedrex is a diet pill that is advertised to give energy, block carbohydrates, raise metabolism and help dieters to lose extra pounds. Identical claims are made by Plexus Block. Dieters are instructed to take one or two capsules twice daily. On average the product carries a hefty price tag of $50 or more for a bottle of 90 capsules. If an individual two capsules twice daily as the label suggests the 90 capsules will last less than a month. The alpha lipoic acid found in Synedrex is regularly referred as an abundant antioxidant because it is both fat and water soluble, it does appear to possibly be useful for fat loss and the prevention of additional fat gain.
- Synedrex does have added vitamins and minerals in addition to the fat burning ingredients.
- The website has nutritional information and other diet related information as well as supplements.
- The website also contains customer reviews and testimonials.
- Synedrex contains copious amounts of caffeine with over 350 mg per dose. This large amount has been known to cause serious jitters, agitation and dehydration when taken over time.
- At over $50 per bottle on average, this is one of the more expensive diet pills on the market.
- There is no real diet plan or exercise plan included on their official site, just the pills to be taken along with a health and fitness plan of the dieter’s choosing.
- Once dieters stop taking the pills, there is the chance that weight could return since there was not a learned modification to eating and lifestyle habits.
Conclusion on SynedrexSynedrex does have many customer reviews and seems to help some dieters to achieve results. It is suggested, as with all diet pills, that users follow a sensible eating and exercise plan to achieve the best results. Overall this looks to be an average diet pill with a very large amount of caffeine in addition to other energy substances. Synedrex is almost like an energy drink in pill form and as such will pose the risks of the same side effects such as agitation, jitters and insomnia as well as dehydration. Read up on Synedrex Side Effects. Similar side effects are often reported with uncertain doses of stimulants like with Adaptogen or Absolute Nutrition Garcinia Cambogia. While the product may provide results it is important to remember that there are much less expensive ways to get caffeine.
Synedrex Questions & Answers:
We refined hundreds of customer comments about Synedrex into this helpful FAQ.
What are the side effects of Synedrex?
Synedrex is another pen name Synedrex goes by. Potential Syne side effects may include nausea, increased blood pressure and jitters, according to some customer reviews.
What is in Synedrex?
Synedrex ingredients are methylxanthine, sulbutiamine, sandalwood extract, yohimbine, alpha lipoic acid , poly-thyronine, chromium, B-vitamins, dipotassium phosphate, silicon dioxide, magnesium stearate, titanium dioxide, gelatin and FD&C blue #1 and green #40.
What are the active ingredient in Synedrex?
The active ingredient in Synedrex are methylxanthine, sulbutiamine, sandalwood extract, yohimbine, alpha lipoic acid, poly-thyronine and chromium.
Does Synedrex work?
There’s no scientific research proving the effectiveness of Synedrex. There are studies linking chromium to weight-loss, but this ingredient is common and can be found online for less than $5.
How much does a bottle of Synedrex cost?
A bottle of Synedrex costs $54.99.
What is Synedrex’s BBB rating?
The BBB rating for Metabolic Nutrition, the company behind Syne, is a concerning “C”.
How do you take Synedrex?
You take one or two Synedrex capsules per day. The website recommends not taking two pills within 15 hours of each other and not taking prior to sleep. A bottle lasts between 22 and 45 days.
Can I take Synedrex if I have a health condition?
Women who are pregnant/nursing, those taking prescriptions medications of any kind, people under 18 years of age or people with health conditions should contact a physician prior to beginning any weight-loss program or diet supplement, including Synedrex. 
What do users like about Synedrex?
Some users like that Synedrex increases energy above their normal levels. Customers also approve of the cost and the fact that you can use the supplement on the go.
What do users NOT like about Syne?
Dieters do not like the idea of side effects with a Synedrex. There are also comments about poor customer service quality and short 30-day return policy.
Who makes Synedrex?
Metabolic Nutrition makes Synedrex.
How do I contact the Synedrex customer service department?
You can contact the Synedrex customer service department by calling 1-954-533-9256, using the customer feedback form on the official website or sending correspondence to Metabolic Nutrition 10318 NW 55th St Sunrise, FL, 33351.
Can I contact Synedrex through social media?
Is Synedrex for men and women?
Both men and women can use Synedrex. The ingredients don’t address specific gender needs.
Do you need to “cycle” off of Synedrex?
You don’t need to “cycle” off of Synedrex. The website recommends stopping use for two weeks after using it for 12 weeks, however.
Do I need to exercise with Synedrex?
You don’t need to exercise with Synedrex, but the company states optimal results occur when you combine with diet and a fitness plan.
Is there a guarantee with Synedrex?
Synedrex offers a 30-day money-back guarantee.
When taking a closer look at weight loss supplements that work best for health and fitness, Leptigen came across as a noticeable product with four ingredients clinically shown to boost energy levels and help the metabolism run at a faster pace, resulting in weight loss.
- 1. Effects of Alpha-Lipoic Acid on Body Weight in Obese Subjects (2011). The American Journal of Medicine. November 1, 2016.
- 2. Effects of Chromium on Body Composition and Weight Loss (1998). International Life Sciences Institute. October 21, 2016.
Synedrex User Tips:
7 Top User Tips
Over the years, we’ve seen that Synedrex users have a lot to say. After analyzing thousands of comments and reviews, these are the tips we think will best prepare you to try this product.
“One piece of advice…try to eat something and drink water because you will get nauseated.” James
“I take it first thing when I get up in the morning around 5:30am and I’m still having some issues staying asleep at night. So when they say take it at least 12 hours prior to bedtime they mean it.” Jennifer
“You do need to push your fluids because it will even push you away from drinking anything too.” Mike
“Whenever I do take a pill I try to take it 20-30 minutes before my work out because that is usually how long it takes to fully kick in, the energy boost is outstanding” Maria
“If you’re sensitive to stimulants and want to try this product I suggest you take it very very early in the morning and with food. Wait at least thirty minutes before you work out.” Angie
“ To lose the weight I have you need a total plan, including healthy eating habits, consistence in workouts, not just a magical pill. Michael
“This product is strong, really strong. I have a real high tolerance for caffeine and could not drink coffee after taking this for about 3 hours.” Debbie
Synedrex Scientific Abstracts:
Testing of the thermogenic reaction of 22mg ephedrine, 30mg caffeine, and 50mg theophylline was studied within human participants with a proclivity to obesity. It was found that the ephedrine/methylxanthines combination were two times as effective as the ephedrine by itself, raising the fasting metabolic rate in all participant groups. It normalized the decreased thermogenic response to a 1.25-MJ meal in participants who were predisposed to obesity. The studies had suggested that small doses of methylxanthines, when combined with ephedrine, could increase the daily energy expenditure of obese participants, largely by fixing their poor thermogenic food response. It had been concluded that ephedrine/methylxanthine could very well be a useful tool in the treatment of obesity. 
30 participants with diabetic polyneuropathy were recruited for this study. They were assigned sulbutiamine or no treatment to test the effects on glycemic control, the severity of neuropathy and electrophysiological parameters at the start of the trial and after the six week period. No substantial improvement in symptom scores was noticed in the groups. However, a significant increase in comparison to the baseline was witnessed in the sulbutiamine group (p< 0.05). Glycemic control in all participants didn’t change and remained consistent throughout the study. The sulbutiamine improved peripheral nerve function in diabetic polyneuropathy, but symptom scores remained the same due to the shortened length of the study. 
Human bladder cancer cells showed a more sanative pro- apoptotic effect to frankincense. Sandalwood oil displayed similar potency when it came to suppressing viability of both UROtsa and J82 cells. Even though both oils had activated similar pathways like inflammatory interleukins (IL-6 signaling), they each had a unique molecular action on bladder cancer cells. The negative regulation of protein kinase activity, as well as G protein-coupled receptors, had been activated by sandalwood oil. In conclusion, sandalwood essential oils had different mechanisms than frankincense. However, both leading to the death of cancer cells.
There had been no remarkable differences in body mass and muscle mass in trials (p > 0.05) following supplementation protocol. The percentage of body fat greatly reduced in the yohimbine participants after protocol (9.3 +/- 1.1 vs. 7.1 +/- 2.2%; p < 0.05). Also, the fat mass had been significantly reduced in the yohimbine as opposed to the placebo group (7.1 +/- 2.2 vs. 9.2 +/- 1.9%; p < 0.05). There were no differences in exercise (bench press, leg press, vertical jump, shuttle run, power test results, and dribble) during trials (p > 0.05). No participants had reported adverse side effects from the yohimbine. The conclusion is that yohimbine supplementation mixed with resistance training doesn’t substantially change body mass or muscle mass or performance indicators. It was found that yohimbine seems to be a useful way for athletes to lose fat. 
- 1. The thermogenic properties of ephedrine/methylxanthine mixtures: human studies (1986). International Journal of Obesity. October 25, 2016.
- 2. Effects of Sulbutiamine on Diabetic Polyneuropathy: An Open Randomised Controlled Study in Type 2 Diabetics (2002). The Malaysian Journal of Medical Sciences. October 25, 2016.
- 3. Differential effects of selective frankincense (Ru Xiang) essential oil versus non-selective sandalwood (Tan Xiang) essential oil on cultured bladder cancer cells: a microarray and bioinformatics study (2014). Chinese Medicine. October 25, 2016.
- 4. Yohimbine: the effects on body composition and exercise performance in soccer players (2016). Research in Sports Medicine. October 25, 2016.
Synedrex Side Effects:
In the world of weight-loss supplements, even natural solutions may not be completely free of side effects. It’s possible to experience a negative reaction to any type of formula. Though Synedrex side effects don’t happen in all users, they do exist for some.
When you feel unsteady, weak, woozy or even faint, it may be a dizzy spell. Dizziness might also be called vertigo and makes it seem like the things surrounding you are spinning.
What causes dizziness?
Dizziness is a symptom of many health issues and a side effect of some medications and supplements. It may be cause by simply standing too fast or something much more serious. Many people associate dizziness with overconsumption of alcohol, migraine headaches and specific medications.
Racing Heart Rate
If your heart feels like it may explode out of your chest or it’s beating very fast, it’s a racing heart rate. This is also known as tachycardia. While a racing heart rate isn’t always serious, sometimes it can be a problem requiring medical attention.
What causes a racing heart rate?
A racing heart rate may be caused by a serious heart condition, poor blood supply to the heart or even emotional stress. It may be a sign of an infection or a heart valve problem. It may also be caused by drug or alcohol abuse or even over use of caffeine. 
A discomfort felt in the abdomen making you feel like you may vomit is known as nausea. It’s a queasy feeling and causes a large amount of discomfort.
What causes nausea?
Nausea may be caused by many different things from something you’ve ingested to a physical injury or even from many different diseases.  Medications and supplements may cause nausea if your body is having a negative reaction. It may also be caused by head injuries, such as a concussion.
The jitters are an uneasy feeling of nervousness or irregular movement. You may feel very unsteady or incredibly anxious.
What causes the jitters?
While the jitters may be caused by anxiety or stress, they may also be caused by ingesting too much caffeine. Certain medications and supplements may also cause the jitters.
Synedrex side effects are not common in all users, but some have reported dizziness, a racing heart rate, nausea and jitters, among others. Make sure you protect yourself by consulting with your doctor before taking any weight-loss supplement, especially if you’re pregnant, nursing, suffer from a medical condition, are taking prescription medication or you’re under 18 years of age.
Syndrex is a thermogenic that’s supposed to increase heat production and thus boost weight-loss. Though side effects aren’t shown to happen often, these are what some users have experienced.
“I was already feeling horrible heat flashes to cold flashes to dizziness and spinning like being drunk and jittery to a sickening point…I went home and by 3 in the afternoon I was puking.” Sarah
“I have had a dull headache, I feel off balance,i dont feel like my mind is clear, it’s crazy.” Pamala
“My heart pounds like crazy even pulsates hard in my neck. I’ve vomited. I’ve had diarrhea.” Dawn
“I felt nausea, jitters, sweats, chills and threw up and couldn’t settle down all day and night…I felt heart palpitations and increased blood pressure and I didn’t even exercise! I didn’t have an appetite because I was so nauseous.” Andrea
“Horrible jitters, and for hours I had severe nausea. The only reason I didn’t vomit was because I didn’t eat anything and stayed very still while taking deep breaths when the urge would hit me. No sleep last night, despite bedtime being 12 hours after I took the ONE pill. Now, the next day, I’m still jittery.” Jennifer
“…I started to vomit like there’s no tomorrow…in less than 3 hours of me taking the pill. My heart is pumping so fast I am having hard time breathing.” Kathy
“…before even beginning my workout routine, my heart rate spiked from a resting rate of 60bpm to 205bpm in about 30 seconds. It lasted for about 30 minutes, before it slowed back to 60bpm.” Mike
“I became dizzy unable to breathe normally my heart was beating so fast it didn’t feel like it was beating at all!! I was sweaty then hot and all my extremities were cold clammy and I felt very panicky.” Shelley
“I became dizzy unable to breathe normally my heart was beating so fast it didn’t feel like it was beating at all!! I was sweaty then hot and all my extremities were cold clammy and I felt very panicky.” Maria
“…the first day I had no appetite just tons of energy. The second day I was nauseated all day…After 7 days I couldn’t take the nausea anymore so I quit taking them. I was constantly nauseated for an entire week without the pills” Corrina
Looking for a supplement that doesn’t give you irritating side effects? We have one you may want to check out. Leptigen is made with clinically tested ingredients and supported by users reviews that consistently report weight-loss.
There comes a time when a supplement deserves a bit more attention, like Synedrex, so we’ll concentrate on Synedrex side effects. Further consideration will be given to ingredients and clinical research. We’ll also analyze hundreds of consumer comments. Afterwards, we’ll summarize the info to give you the bottom line.
What You Need to Know
To start, Synedrex is a fat burner containing caffeine, sulbutiamine, yohimbe extract, methylxanthine, sandalwood extract, alpha lipoic acid, poly-thyronine and B-vitamins, among others. The recommended serving is one capsule per day, which supposedly results in increased weight-loss. One of the benefits is ease of use.
The product, introduced as a fat burner by Metabolic Nutrition more than 25 years ago, appears to include some natural ingredients, a good start. You can shop for Synedrex on the official website and through online retailers. We like that the company has a strong position in the market and that we located some positive customer comments, but read on…
The first issue with Synedrex side effects is skin irritability. “One of the main purposes of weight-loss is to love the skin you’re in,” said our Research Editor. “If a supplement like Synedrex leaves you irritated, that may be a sign to try another product.”
“I took it and within 30 min. I felt like my face was on fire…then that sensation spread to my arms then my stomach. When I looked in the mirror after I felt my lips tingling I seen I started breaking out in hives,” commented a dieter.
“I took 1 pill of Synedrex yesterday at 1:30 pm and 30 minutes later I felt hot all over. I had tremors and I couldn’t really focus,” said a user.
Increased Heart Rate – “Yikes!”
Based on customer comments, Synedrex side effects include increased heart rate. “I became dizzy unable to breathe normally my heart was beating so fast it didn’t feel like it was beating at all!! I was sweaty then hot and all my extremities were cold clammy and I felt very panicky,” commented a user.
“I recently started taking these pills and now I’m going to stop. I started feeling very faint, dizzy, sweaty and nauseous, all of the symptoms that EVEN the label on the bottle tell you can happen. Happened to me,” reported a customer.
“It gives you an intense level of energy, but at the cost of jittery, shaky, anxiety filled days with a heart that feels like it’s going to give out. I’ve taken it 6 days a week for 6 weeks, but I’ve been forced to quit due to the compounded side effects, and the different ones that start appearing the more you take them. Headaches, nausea, insomnia,” said a consumer.
Throughout our extensive research of supplements, we’ve found that something small, like increased heart rate, could reduce the chances of long-term success. If Synedrex causes negative reactions of any kind, there’s a concern .
According to the Synedrex website, the formula in the supplement is scientifically engineered, meaning the product is supposedly linked to clinical research. After a bit more investigation, we couldn’t locate studies supporting the claims. What we did find was information on sulbutiamine, an ingredient in Synedrex. According to the National Institutes of Health, side effects may include headache, constipation, dry mouth, back pain, nervousness and difficulty falling asleep, among others. At DietSpotlight, finding evidence a weight-loss product works is critical. If a company can’t provide all of the details, we have to walk away.
The Bottom Line
After taking a close look at Synedrex, here’s our decision. We like that the company has been in business for decades and that we found some positive customer comments, but we can’t recommend it because there’s no published clinical research supporting weight-loss claims [2 ]. Plus, we’re also concerned that increased heart rate and skin irritability could cause bigger concerns .
If you’d like to lose those extra pounds, we recommend going with a supplement supported by published clinical research, with no one reporting negative side effects .
Leptigen is one of the best supplements we’ve researched in 2016. The product contains a formula consisting of a four-ingredient proprietary blend, which has been shown in published scientific studies to help dieters increase metabolism and ignite fat loss [5, 6 , 7 , 8]. No one is reporting negative side effects and comments on the web highlight dieters seeing exceptional results.
The company that makes Leptigen is so confident in the supplement, they’re providing a Special Trial Offer, an excellent choice.
Synedrex is a "Powerful Stimulant" that claims it can boost metabolism, cut fat and even smooth out lines. There is a Science Center, but we didn't find any compelling science or research of any kind. The fact that caffeine is a big part of the formula is clear, but you're not told just how much is included.
Synedrex Ingredients and Supplement Facts
Serving Per Container: 45
|Amount per Serving||% DV|
|- Methylpentane Citrate||*||*|
|- Sandalwood Extract||*||*|
|- Yohimbine Extract||*||*|
|- Alpha Lipoic Acid||*||*|
Other Ingredients: Dipotassium phosphate, microcrystalline methyl cellulose, silicone dioxide, magnesium stearate, titanium dioxide, gelatin
We researched Synedrex ingredients in order to give you the information you need.
Methylxanthine, also known as xanthine, is a chemical found naturally in body tissues and fluids.
What Is It Supposed To Do?
The main purpose of methylxanthine is increasing alertness in the nervous system, although it may also help asthma.
According to a study published in Canadian Journal of Applied Physiology, “The effects of ephedrine, in conjunction with methylxanthines and aspirin, in humans appear unequivocal but include various cardiovascular side effects. None of these compounds have been tested for their effectiveness or safety over prolonged periods of time.” 
You may want to try Leptigen, which has clinically tested ingredients.
Sulbutiamine is a chemical containing two thiamine molecules. It is thought to be found in the brain.
What Is It Supposed To Do?
Not to be confused with sibutramine, an appetite suppressant, sulbutiamine is a compound used for memory, fatigue, and the health of the nervous system.
According to information published by the American Society of Health System Pharmacists, “Although thiamine has not been shown by well-controlled trials to have any therapeutic value, the drug has been used for the management of poor appetite, ulcerative colitis, chronic diarrhea, other GI disorders, and the cerebella syndrome.” 
Also known as East Indian sandalwood, the sandalwood tree, where the sandalwood extract is derived from, is not easy to grow due to the specific conditions it needs for proper cultivation.
What Is It Supposed To Do?
Sandalwood extract is used traditionally for aromatherapy, spiritual use, and commercially for perfumes.
In a study published Phytotherapy Research, researchers concluded about sandalwood extract that, “However, until further studies are conducted to determine safety regarding internal use, this herb warrants caution with use.”
Yohimbe is a tree found in Africa. The bark is used to make medicines.
What Is It Supposed To Do?
Yohimbe has been used for a wide variety of treatment, including erectile dysfunction, depression, athletic performance, weight-loss, high blood pressure, and much more.
In a study published in Research in Sports Medicine, researchers studied the effects of yohimbe on athletes. In conclusion, “Nonetheless, yohimbine supplementation appears to be suitable as a fat loss strategy in elite athletes.” This does not hold promising results for those who are not at this level of exercise.
Is There Anything Out There That TRULY Works?
Before you give up on weight-loss, we suggest you try the Special Trial Offer from Leptigen. They have clinically-tested ingredients and consistently positive customer reviews. Click here to try out the supplement.