Is Phentermine A Stimulant? (does it have a strong one?)

January 8, 2024 |

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Regular exercise and eating a reduced-calorie but well-balanced diet are among the foundations of weight loss, but there are certain drugs or medications that can provide powerful support. One of these is phentermine, known to be among the most popular weight-loss drugs. Is phentermine a stimulant and how does it work?

Yes, phentermine is a stimulant! It’s one of the two stimulants approved by the FDA (Food and Drug Administration) for weight loss and obesity. But you can’t just drink it anytime you want to because it’s a controlled substance. Plus, it comes with risks, side effects, and possible legality issues.

Can anyone use phentermine?

How does it work, what drugs or substances does it interact with, and can you use it for several months?

We prepared this article to provide you with answers to the FAQs about phentermine and help you find alternatives that can be safer and might be more ideal for you.

That’s not all. We also prepared a guide on what drugs or substances to avoid, tips on what you should do, more tips to keep you safe while using phentermine, and better, healthier alternatives to try.

Let’s learn more about them below.

Is Phentermine A Stimulant?

Phentermine formula

Phentermine is a prescription weight-loss drug intended for use as part of a weight-loss plan. It’s used to suppress appetite, decrease your hunger, and make you feel full longer.

It works by activating your sympathetic nervous system, the part of your brain that’s responsible for the so-called “fight or flight” response. This mode of action makes phentermine a “sympathomimetic” drug or “stimulant.”

The exact mechanism of how phentermine works remain unclear, with experts still unsure how it happens.

However, it is believed that the drug might have multiple effects on the brain.

One possible mode of action is that phentermine helps in the release of chemicals called catecholamines in the hypothalamus (a part of the brain).

It can also stimulate the brain to produce called neurotransmitters (examples are norepinephrine, serotonin, and dopamine), making you feel less hungry. These neurotransmitters are similar to adrenaline, so don’t be surprised if you feel an “adrenaline rush” after taking phentermine.

What Kind Of Stimulant Is Phentermine?

Phentermine is a CNS stimulant or central nervous system stimulant.

These types of stimulants work by increasing the levels of neurotransmitters and other chemicals in the brain that promote increased alertness, energy, attention, and physical activity.

What Does Phentermine Do To The Body?

As a stimulant, how can phentermine affect your body?

Some researchers believe that the drug can affect metabolic processes, leading to weight loss. However, the mechanism of action for that effect is unknown.

What’s known, however, is that phentermine can affect your body after it stimulated your brain.

Because the brain also controls other body processes, phentermine and other CNS stimulants can increase your breathing rate, heart rate, and blood pressure.

People who take phentermine can experience healthy reductions in blood pressure, blood sugar, and other obesity-related issues. These effects are believed to be due to weight loss, not a direct effect of the drug itself.

Learn more about its effects on your body, including possible harmful side effects or risks below.

Does Phentermine Give You Energy?

Yes. As a stimulant, phentermine helps you feel more energized and possibly more motivated to go out for a run or hit the gym.

Remember that “fight or flight” response?

Phentermine stimulates your brain to release adrenaline and other neurotransmitters that make your body feel extra alert and ready for anything.

The mechanism is rather simple. With the adrenaline boost, your body’s glucose levels increase and fat is broken down to produce energy. Your heart rate increases and more blood is pumped through your body.

You’re now ready to face the danger or run away as fast as you can.

But because there isn’t a real danger, your body doesn’t need to fight or flee. Instead, you get an extra energy boost that you can use for working out.

However, the energy boost isn’t the same for everyone. And even if you experienced an adrenaline rush that makes you feel energized, it could quickly wane.

Appetite Suppression

The drug might also increase the levels of leptin, a hormone that makes us feel full, and reduce the effects of neuropeptide Y designated as the chemical messenger that makes us feel the urge to eat, decreases energy use and increases fat storage.

Weight Loss: Does Phentermine Burn Fat Or Muscle?

No. It doesn’t directly burn fats or muscles. Instead, it’s an appetite suppressant.

This reduces appetite and leads to reduced food consumption. By eating less, your body might burn more calories than you’re eating, possibly leading to weight loss.

However, because it doesn’t target fat burning, phentermine use might lead to muscle loss.

Why Does Phentermine Make You Feel High?

That’s because it causes the release of more norepinephrine, dopamine, and serotonin. These brain chemicals or neurotransmitters can produce an effect similar to amphetamine, creating the feeling of being “high.”

Your next question might be: then why is it making me feel so tired?

Well, that’s an adverse effect of overstimulation. After feeling so “high” and energized, your body can experience reduced energy levels, drowsiness, and fatigue. That’s especially true if you weren’t able to sleep well due to insomnia from taking this drug.

Does Insomnia From Phentermine Go Away?

As a stimulant, phentermine might keep you awake for hours, even if it’s already your bedtime.

The good news is that it’s a side effect that can go away after you’ve been using this medication for several weeks.

So, to prevent insomnia while taking this substance, try to avoid taking phentermine late in the afternoon or evening so that your body can still process the drug long before bedtime.

Should You Take Phentermine?

The answer actually depends on several factors, including your health, current weight, exercise or workout routines, weight loss goals, etc.

IMPORTANT: People who take stimulant drugs like phentermine for weight loss have a higher risk of developing increased blood pressure in their lungs, a condition called pulmonary hypertension.

This condition is rare but often deadly because it leads to breathing difficulties. Talk to your doctor.

If you decide on using phentermine, you should make sure you don’t have any of the underlying medical conditions listed below. Your doctor might also run tests to make sure you don’t have an undiagnosed medical condition.

Contraindications & Reasons Why You Shouldn’t Take Phentermine

Phentermine (alone or in combination) is a drug that isn’t indicated for children below 16 years of age, even if they fit the criteria above.

It’s also important to tell your doctor about any health condition, medication you’re taking, and allergies to any drug, food, or substance. This helps them adjust the dosage or stop phentermine use until it’s safe for you to take it.

It’s also not advisable if:

  • You’re pregnant, planning to get pregnant, or breastfeeding
  • You’re allergic to topiramate and the other ingredients in your chosen phentermine brand

Phentermine shouldn’t be used by anyone with a medical history of the following:

  • Abnormal or irregular heartbeat
  • High blood pressure
  • Stroke
  • Heart failure, heart valve disorder, or coronary artery disease
  • Glaucoma (eye condition usually caused by abnormally high pressure in your eye)
  • Drug abuse
  • Kidney disease (especially if you’re undergoing dialysis)
  • Thyroid problems, such as hyperthyroidism
  • Parkinson’s disease
  • Tourette syndrome
  • Seizure disorders
  • Depression (drinking phentermine together with depression drugs can lead to very high blood pressure)
  • Diabetes or high blood sugar (phentermine can cause a dangerous drop in your blood sugar levels if you’re already taking diabetes medications)

As a general rule, phentermine should be avoided by anyone with a severe medical condition.

There’s limited data on phentermine’s safety with patients over 65 years of age. Extra care should be taken before they use this drug, especially because they might respond differently than younger users and are more likely to have a still undiagnosed medical condition.

That’s not all!

You should also be prepared for the side effects that you might experience after taking this stimulant.

Let’s check them out below.

Phentermine Side Effects

It’s not the same for everyone, but you might experience the following side effects:

  • Constipation or diarrhea
  • Dizziness
  • Headache
  • Feeling nervous
  • Restlessness
  • Dry mouth
  • Bad taste in your mouth
  • Trouble sleeping
  • Reduced interest in sex
  • Erectile dysfunction

It’s also possible to experience side effects that aren’t listed above. Call your doctor if you have concerns about the possible side effects of the phentermine drug you’re taking.

Emergency: When To Call Your Doctor?

Don’t ignore any of these emergency signs after taking phentermine or any medication:

  • Mood changes
  • Signs of low blood sugar: shaking, headache, dizziness, feeling sleepy or weak, a fast heartbeat, sweating, confusion, or hunger
  • Signs of an allergic reaction: rash, hives, wheezing, unusual hoarseness, itching and red or swollen skin with or without fever, tightness in your throat or chest, trouble breathing or swallowing, and/or swelling of your face, lips, mouth, tongue, or throat
  • Signs of high blood pressure: dizziness, passing out, migraine (a very bad headache), or change in eyesight (blurry)
  • Signs of a heart-related emergency: fast or abnormal heartbeat, dizziness, chest pain, fatigue (a weakness that doesn’t go away), trouble breathing, shakiness, or swelling in your arms or legs

Does Phentermine Cause Anxiety & Mental Problems?

Yes. Studies show that this drug can cause or increase your risks of anxiety, depression, and other mood disorders.

It might also induce psychosis.

Phentermine Overdose

It’s very important to only take the recommended dose and follow your doctor’s instructions. In case of a missed dose, immediately take the missed one. However, if the missed dose is over 24 hours ago, it’s better to skip it.

Never take two doses at the same time because that can lead to an overdose or other health concerns.

Because it’s a stimulant, the effects can be severe.

Symptoms of an acute phentermine overdose can include:

  • Tremors
  • Restlessness
  • Confusion
  • Rapid breathing
  • Panic
  • Hallucinations
  • Fatigue
  • Depression
  • Hypotension (low blood pressure) or hypertension (high blood pressure)
  • Irregular heartbeat
  • Diarrhea
  • Vomiting
  • Abdominal cramps

Chronic intoxication symptoms can include:

  • Hyperactivity
  • Irritability
  • Marked insomnia (severe sleeping problems)
  • Severe skin lesions
  • Irritability
  • Psychosis (delusions or hallucinations)

Phentermine overdose can be deadly. Severe cases can lead to convulsions, coma, or even death.

Call emergency services or the Poison Helpline at 1-800-222-1222.

Drug Interactions

If you’re taking any of these medications or drug components, then you can’t use phentermine:

  • Oral contraceptives (might cause irregular bleeding)
  • SSRIs – selective serotonin reuptake inhibitors such as Paxil (paroxetine), Prozac (fluoxetine), Luvox (fluvoxamine), and Zoloft (sertraline)
  • MAOIs – monoamine oxidase inhibitors such as Marplan (isocarboxazid) and Nardil (phenelzine)
  • Linezolid
  • Procarbazine
  • Tranylcypromine
  • Selegiline
  • Rasagiline
  • Amphetamine
  • Antacids
  • Epinephrine
  • Dopamine
  • Amantadine
  • Desmopressin
  • Antihypertensives (such as beta-blockers)
  • CNS (central nervous system) depressants such as benzodiazepines, barbiturates, and sleep medications

Don’t ever take two stimulants together.

It can also interact with other diet medications or natural supplements:

  • American ginseng
  • Guarana
  • Eucalyptus
  • Yerba mate
  • Sage

It’s very important to tell your doctor about any drug or medication that you’re taking, including prescription, over-the-counter, or natural and herbal remedies, even if these aren’t listed above.

Some components of these drugs might interact with each other, leading to significant health risks. Others might make phentermine less effective.

Stimulant Withdrawal Symptoms & Other Effects Of Drug Abuse

Because stimulants like phentermine can make a person feel high, it also has a higher risk or potential for drug abuse.

You shouldn’t abruptly stop using phentermine because it can lead to severe withdrawal symptoms such as mental depression and extreme fatigue.

The FDA recommends appropriate medical monitoring if you need to abruptly stop using phentermine for any reason, such as severe side effects.

Other possible withdrawal symptoms can include:

  • Lack of energy
  • Headaches
  • Diarrhea
  • Stomach pain
  • Vomiting
  • Heart palpitations
  • High blood pressure
  • Insomnia
  • Irritability
  • Memory loss
  • Menstrual irregularities

Although phentermine medications can help you achieve your weight loss goals, it’s important to acknowledge that they have several potential risks.

Aside from drug dependence, you might find it difficult to concentrate without taking phentermine or unhealthy cravings can push you to take more than you need.

Because these ill practices can be dangerous to your cardiovascular system, it can be good to seek help from a mental health professional or find a support group. Your doctor should also know, so they can adjust the dosage if needed.

So, what do we recommend?

Healthier, Safer, & Legal Alternative To Phentermine

Phentermine might be effective but we’re worried about the side effects and safety risks we mentioned above. Considering its status as a controlled substance that can lead to drug abuse, it isn’t something that we’d recommend for you to use.

Why not try PhenQ?

Its main ingredient is the patented a-LACYS RESET, which can boost your slimming efforts naturally.

The a-LACYS RESET compound is made of compounds alpha-lipoic acid and cystine that encourage your body to get rid of fats naturally.

What’s great about PhenQ’s active ingredient is that it doesn’t just encourage natural weight loss, it also has other benefits because of its healthy ingredients:

  • Anti-aging properties (because it fights oxidative stress)
  • Improves ATP production (to power up cellular processes)
  • Burns fat
  • Reduces protein catabolism (that means it doesn’t burn muscles, only fat)
  • Improves muscle mass
  • Controls lactic acid build-up during exercise to reduce the burning sensation in your muscles
  • Fights fatigue
  • Increases your well-being
  • Improves lipolysis and anabolic functions for muscle growth and repair
  • Rebalances metabolic disorders

Plus, aside from having a-LACYS RESET, PhenQ also contains other natural metabolism-boosting ingredients to further promote healthy weight loss:

  • Caffeine – promotes thermogenesis (heat production by burning calories) to help shed off excess fat stores
  • L-carnitine fumarate – helps shed off excess fats and combat mental and physical exhaustion
  • Nopal cactus fiber – makes you feel full with less food and also binds with dietary fats for natural elimination from your body
  • Chromium picolinate – an appetite suppressant like phentermine that curbs your cravings for carbs and sugars
  • Capsimax powder – supports natural fat-burning production and promotes thermogenesis

You don’t need a prescription to order PhenQ because it doesn’t contain phentermine. Plus, it’s made of 100% natural and safe ingredients for your peace of mind. It’s even suitable for vegans and vegetarians.

As a natural dietary supplement, it doesn’t have known interactions with oral contraceptives or any medicines. The brand also boasts of a strong safety record with no reported side effects so far.

However, it’s best to consult your doctor if you’re pregnant or have an underlying medical condition before using PhenQ.

Final Thoughts

So, is phentermine a stimulant? The answer is both yes and no. It depends on how you look at it. Phentermine does have stimulating effects, but it’s not as strong as some other stimulants.

If you’re looking for a natural alternative to phentermine that still has powerful weight loss and appetite suppressing effects, consider trying PhenQ.

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