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Phentermine Over The Counter 2023: 5 Best Natural OTC Alternatives

Markita Lewis

Updated on - Written by
Medically reviewed by Kathy Shattler, MS, RDN

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  • Clinically studied trademark ingredient
  • Small daily dosage
  • 60-day money-back guarantee

Up To 50% Off When Buying In Bulk



  • Transparent about ingredient list and dosing
  • All ingredients are clinically effective
  • High customer satisfaction ratings

Up to 55% Off When Buying in Bulk



  • Contains well-studied ingredient glucomannan
  • Transparency in formula’s ingredients and dosing
  • Low in stimulants

Phentermine over the counter is necessary when losing weight and extra fat can be a difficult journey. In fact, sometimes you need an extra boost to get over the plateau in order to reach your body goals.

Effective dieting pills are available by a doctor’s prescription, but the difficulties of accessing today’s medical system and the unpleasant side effects from some of these medications like phentermine can be concerning.

It is understandable that people want to lose weight with an effective over-the-counter phentermine alternative that’s made with only natural ingredients.

This article looks at 5 of the best phentermine over-the-counter natural alternatives available in 2022.

Best Natural OTC Alternatives On The Market In (June. 2023)

What Is Phentermine?

Phentermine is a prescription medication[1] first introduced in 1959 to support short-term weight loss. It works by stimulating neurotransmitters in the central nervous system to decrease appetite. Phentermine is often combined with topiramate, an anticonvulsant medication that increases phentermine’s ability to act as an appetite suppressant.

Phentermine diet pills are currently only available by prescription for certain people. The FDA approved phentermine/topiramate[2] in 2012 to be used by individuals with a BMI (body mass index) over 30 kg/m2 or with a BMI over 27 with at least one weight-related comorbidity.

Does It Help With Weight Loss?

There is a long history of research[3] to show the benefits of phentermine and phentermine/topiramate[4] for promoting weight loss.

Studies with phentermine alone find that people taking phentermine long-term[5] may experience an average 7.4% weight loss from initial body weight.

In a 56-week clinical trial[6], people receiving the highest dose of phentermine/topiramate lost an average of 10.2 kg (22.4 lbs) and were more likely to lose over 5-10% of their initial body weight.

5 Best OTC Phentermine Alternatives To Buy 2023



Up To 50% Off When Buying In Bulk

See PhenQ Reviews

Created by the trusted brand Wolfson Brands Ltd, PhenQ has a unique blend of clinically backed ingredients to help you lose weight and burn fat.

  • Clinically studied trademark ingredient
  • Small daily dosage
  • 60-day money-back guarantee
  • Proprietary blend of ingredients
  • No third-party testing

PhenQ is a weight loss pill supplied and manufactured by Wolfson Brands (UK) Limited, a brand that combines cutting-edge science and time-tested strategies from athletes and professionals into products and information.

PhenQ claims to work by boosting fat burning, reducing fat production, suppressing appetite, boosting energy, and improving mood.

One of the main ingredients in the PhenQ formula is ɑLacys Reset, a trademarked formula created by Nutraceuticals International Group.

A-Lacys Reset combines alpha-lipoic acid and cysteine, ingredients that promote weight loss[7] and fight oxidative stress[8].

Though the referenced study could not be located, PhenQ states that in clinical studies, people taking 𝝰-Lacys Reset lost 7.4% body fat, and 3.44% body weight, and increased muscle mass by 3.8% compared to placebo and other ingredients.

Other major ingredients in PhenQ’s proprietary blend include Capsimax Powder (capsicum, piperine, caffeine, and niacin), chromium picolinate, caffeine, nopal (cactus), and L-carnitine fumarate.

PhenQ does not need to be cycled, is vegetarian and vegan friendly, and has reported no side effects or medicine interactions.

A 30-day supply (60 pills) of PHenQ costs $69.99. Additional discounts are available if you purchase in bulk.

PhenQ has a 60-day money-back guarantee.



Up to 55% Off When Buying in Bulk

See PhenGold Reviews

If you’re looking for a high-potency fat burner, then PhenGold may be right for you. This stimulant-powered supplement is filled with the maximum doses of well-studied metabolism boosters.

  • Transparent about ingredient list and dosing
  • All ingredients are clinically effective
  • High customer satisfaction ratings
  • Has multiple sources of caffeine
  • The 100-day money-back guarantee only applies to bulk purchases

PhenGold comes from Swiss Research Labs, a health and wellness brand focused on scientific research.

This weight loss pill is formulated to improve fat burning, boost metabolism, curve cravings and appetite, boost energy and focus, and enhance mood.

The ingredients in PhenGold are green tea, green coffee bean extract, L-tyrosine, Rhodiola Rosea, caffeine (225 mg), DMAE, L-theanine, cayenne pepper, vitamins B3, B6, and B12.

A unique aspect of this supplement is that it is reported to contain the maximum strength dosage of its main ingredients to help you lose weight. Somehow, the manufacturers managed to fit these ingredients into a 3-pill dose.

It’s important to note that PhenGold contains three caffeine sources (green tea, green coffee bean extract, and caffeine), which could make this product unsuitable for people with caffeine sensitivities. It is highly recommended to avoid other stimulants or stimulating products while taking PhenGold.

A one-month supply of PhenGold (90 capsules) costs $79.95. At the time of writing this article, PhenGold is on sale for $59.99. Additional discounts are available for bulk purchases.

PhenGold offers a 100-day money-back guarantee, but this does not apply to the one-month supply.


Leanbean is considered the #1 fat burner for women because it is tailored for women’s needs. This low-stimulant supplement is powered by glucomannan and other effective ingredients.

  • Contains well-studied ingredient glucomannan
  • Transparency in formula’s ingredients and dosing
  • Low in stimulants
  • Potentially large dosage (up to 6 capsules)
  • Must take the supplement for 90 days for a refund

Leanbean comes from Ultimate Life Ltd, a company with a mission to provide natural solutions that suit the demands of modern women and female performance.

Through its unique formula, Leanbean reduces food cravings and calorie intake, supports fat metabolism, and boosts energy and mental focus.

The main ingredients in Leanbean are glucomannan (3g), choline, vitamin B6 and B12, chromium picolinate, zinc, chloride, green coffee bean extract, turmeric, Garcinia cambogia, acai berry, and piperine.

The standout ingredient in Leanbean is glucomannan, a soluble dietary fiber that is consistently shown in studies[9] to be an appetite suppressant and effective for weight and fat loss. 

Leanbean also stands out by being significantly lower in caffeine compared to other fat burners, and it is third-party tested. This supplement can be cycled and is vegan, gluten-free, and soy-free.

A one-month supply (180 capsules) of Leanbean is $59.99. The popular Complete Bundle is a 4-month supply that also comes with a downloadable workout guide and meal plan for $189.97.

Leanbean’s 90-day money-back guarantee has caveats: you must buy the complete 4-month bundle and take six capsules daily for 90 days before getting a refund.


Phen24 is a unique supplement system that works with your body’s hormones and circadian rhythms to help you lose weight around the clock.

  • Unique system targeting metabolism and hormones
  • The product has a 60-day money-back guarantee
  • The supplement is from a trusted brand
  • No third-party testing
  • Not safe for people with certain medical conditions or medications

Phen24 is a two-part metabolism fueling supplement from Wolfson Brands (UK) Ltd. It was formulated by Angela MacRitchie, a certified herbalist, nutritionist, and naturopath.

While most fat burners focus on the energy-burning capabilities of your mitochondria, Phen24 targets the hormones that make it difficult to lose weight.

Cortisol is a stress hormone that can disrupt your body’s natural sleep-wake cycles (circadian rhythms[10]), influence metabolism and food intake[11], and cause fat and weight gain[12].

Phen24 comes in a set – a Daytime formula and a Nighttime formula meant to help balance cortisol levels, support a normal circadian rhythm, and improve your metabolism during the day and night to promote weight loss.

The Daytime formula contains zinc, manganese, copper, iodine, caffeine, guarana extract, l-phenylalanine, and cayenne. Together, these ingredients increase thermogenesis, help boost energy levels, and improve exercise performance. 

The Nighttime formula has vitamin C, biotin, chromium, thiamine, vitamin B6, calcium d-pantothenate, glucomannan, Griffonia extract, choline, green tea extract, and hops extract. This formula is made with ingredients to reduce stress, increase restful sleep, and decrease nighttime food cravings.

One box contains a bottle of daytime (30 capsules) and nighttime (60 capsules) Phen24 for a 30-day supply. A box costs $84.99, is currently on sale for $74.99. You can save more if you buy in bulk.

Purchases come with a 60-day money-back guarantee.


If you’re looking for an affordable fat-burning supplement to get lean and maintain your muscle mass, PrimeShred is formulated with clinically backed ingredients to help you meet your goals.

  • Transparency about ingredient dosing
  • No artificial colors, preservatives, or sweeteners
  • Affordable in pricing
  • High in caffeine from multiple sources
  • A 100-day money-back guarantee does not apply to a one-month supply

PrimeShred is a weight loss pill that comes from Health Nutrition Ltd., a company that has been developing health and fitness supplements since 1999. PrimeShred is marketed as a hardcore fat burner for men, but it is also safe for women to use. This supplement is reported to increase thermogenesis, boost metabolism, and improve energy and focus.

PrimeShed’s ingredients include green tea extract, l-tyrosine, l-theanine, Rhodiola Rosea root, caffeine anhydrous, cayenne pepper, DMAE, green coffee, vitamin B3, B6, and B12, and Bioperine. All of the active ingredients in PrimeShred are transparently dosed so that you can see what you’re getting in each dose. PrimeShred contains green tea extract, caffeine anhydrous, and green coffee, making this supplement high in caffeine.

PrimeShred is vegetarian, vegan-friendly, and free of soy, gluten, and GMOs. They have a 100-day, 100% money-back guarantee on their bulk-purchased products.

Potential Side Effects

Just because these over-the-counter (OTC) phentermine pills are made with natural ingredients doesn’t mean that there isn’t the potential to feel side effects.

Here are some potential side effects from some common ingredients found in these natural  alternatives:

  • Garcinia cambogia: potential side effects[13] include leg cramps, diarrhea, gas, heartburn, rash, general weakness, headache, menstrual bleeding, acute pancreatitis, hepatoxicity (liver toxicity), serotonin toxicity, and psychosis
  • Rhodiola rosea: may cause[14] dizziness and gastrointestinal discomfort
  • Caffeine: should be limited to 400 mg daily and may cause side effects[15] including insomnia, headache, diarrhea, upset stomach, anxiety, dizziness, and increased heart rate.
  • DMAE: in high doses, may cause[16] insomnia, muscle tenseness, spontaneous muscle twitches
  • Guarana: when combined with other ingredients, may cause[17] agitation, anxiety, gastrointestinal upset, aggression, cardiorespiratory arrest, and metabolic acidosis

Glucomannan: can cause[18] esophagus blockages, diarrhea, loose stools, and other gastrointestinal distress.

Choose The Best Phentermine Alternatives

We’ve chosen some of the best phentermine over-the-counter supplements on the market, but you should also be informed about what makes a good supplement.

Transparent About Ingredients And Dosing

You should know what’s in your supplement before you buy it. The best supplement brands should list the dosage of each ingredient used in their formula. This can help you be sure that you’re receiving ingredients in clinically-relevant doses. It is difficult to tell whether you are getting your money’s worth when you have proprietary blends.

Some over-the-counter phentermine supplements are high in caffeine and caffeine-containing ingredients, and transparency about the dosing can help you determine if it’s a good choice for you.

Uses Science-Backed Ingredients

A long ingredient list may seem impressive, but it doesn’t mean anything if the ingredients aren’t effective. Choose over-the-counter phentermine supplements that use only science-backed ingredients instead of fillers. Many brand websites will have links to clinical studies that show the effectiveness of individual ingredients.

Manufacturer Reputation

The supplement industry is large, and not all companies are out for your best interest. If you’re going to buy any supplement, check out the brand’s background. Have they been around for a few years? Are customers happy with their products? Does the manufacturer have other supplements that are well-known and trusted? These are all important questions to ask.

A manufacturer should also have a good return policy for their customers so that they’re not predatory in taking your money.

Third-party Testing

When possible, look for brands that have been third-party tested. Third-party testing means that an independent lab has looked at the manufacturing process of a supplement and made sure that it is up to good standards. Popular certifying organizations that use third-party tests include USP, NSF International, and ConsumerLab.com. But supplement manufacturers can get their products tested by an independent third-party lab and still offer some guarantee of safety and certainty in the quality of the ingredients without being certified by an organization.

Value For Price

A higher price does not always mean that it is a better supplement. Never try to break the bank for your supplement – choose something within your price range to use long-term if needed.

When you’re checking to see if a phentermine alternative is worth the price, consider factors like the ingredients included, brand reputation, third-party testing, and your budget.

Final Thought

Phentermine is an effective weight loss medication for many, but it does come with certain health risks. Choosing an over-the-counter phentermine supplement may help you achieve weight loss and a leaner physique with a lower risk of side effects.

When looking for a phentermine diet pill, look for brands that are trusted, have transparent ingredient lists, and are made with trusted ingredients. Some of these weight loss supplements have their own risk by being high in caffeine, but they can be taken safely. Alternately, low-stimulant supplements are available.

For effective weight loss and fat burning, weight loss supplements should be combined with healthy habits like eating a low-calorie diet with nutrient-dense foods and getting regular exercise. Supplements like these are supports for the bigger picture.

Before starting any new supplement, speak with your doctor to see if it is safe for you to use.

Frequently Asked Questions

What is phentermine?

Phentermine is a prescription weight-loss drug that supports short-term weight loss. It works by stimulating neurotransmitters in the nervous system to decrease appetite.

Why choose a phentermine alternative over phentermine?

Phentermine is only available by prescription for adults with a BMI over 30 kg/m2 or with a BMI over 27 with at least one weight-related comorbidity and has more side effects. OTC phentermine can be more accessible with fewer side effects, making them an attractive alternative.

How do phentermine alternatives help you lose weight?

Most phentermine alternatives help support the function of your mitochondria, increase fat burning, decrease fat production, reduce appetite, and increase energy.

What should you avoid taking with phentermine diet pills?

If you take a phentermine alternative with a high concentration of stimulants, avoid having any caffeine or additional stimulants. Some supplements may interact with the medications that you take. If you notice any medication interaction while taking over-the-counter (OTC) phentermine supplements, discontinue the supplement and speak with your doctor.

How long does it take to see results from phentermine diet pills?

Depending on which over-the-counter phentermine supplement you choose, it may take as little as a month to see results. Otherwise, it may take up to a few months to see results. Combine your supplement with a healthy, low-calorie diet, exercise, and a healthy lifestyle to see faster results.

+ 18 sources

Health Canal avoids using tertiary references. We have strict sourcing guidelines and rely on peer-reviewed studies, academic researches from medical associations and institutions. To ensure the accuracy of articles in Health Canal, you can read more about the editorial process here

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Markita Lewis

Written by:

Markita Lewis, MS, RD

Medically reviewed by:

Kathy Shattler

Markita Lewis, MS, RD is a registered dietitian and a freelance health and wellness writer practicing in the Los Angeles area. As a clinician, Markita has several years of experience working with adult and pediatric patients in inpatient and outpatient settings. Markita has also conducted research in areas including diverticulosis, age-related macular degeneration, and cultural eating patterns.

Medically reviewed by:

Kathy Shattler

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