When considering medications for weight loss or attention deficit hyperactivity disorder (ADHD), two names that often come up are Phentermine and Adderall. While both drugs are stimulants, they are approved for different primary uses and have distinct characteristics. Understanding How Strong Is Phentermine Compared To Adderall involves looking at various factors, including their approved uses, mechanisms of action, dosages, side effects, and safety profiles. This article provides a comprehensive comparison to help you understand the nuances between these two medications.
Understanding the Strength of Stimulants: Phentermine and Adderall
The concept of “strength” when comparing medications isn’t straightforward. It can refer to effectiveness, potency in achieving a specific effect, the intensity of side effects, or the potential for abuse. Both Phentermine and Adderall are classified as central nervous system (CNS) stimulants, but they differ significantly in their intended uses and regulatory classifications.
Adderall, a brand name for amphetamine/dextroamphetamine, is primarily prescribed for ADHD and narcolepsy. It’s a Schedule II controlled substance in the U.S., indicating a high potential for abuse and dependence. Phentermine, on the other hand, is mainly used for short-term weight loss in individuals with obesity. It is classified as a Schedule IV controlled substance, suggesting a lower, but still present, potential for abuse compared to Schedule II drugs.
| DRUG | ADDERALL | PHENTERMINE |
|---|---|---|
| APPROVED USE | ADHD/Narcolepsy | Weight Loss |
| OFF-LABEL USE | Fatigue, Weight Loss | ADHD |
| DRUG CLASS | Schedule II (Boxed Warning) | Schedule IV |
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Primary Uses: Where Each Drug Shines
While both Adderall and Phentermine are stimulants, their primary approved uses are distinct, reflecting their differing strengths and focuses.
Adderall: Focus and ADHD/Narcolepsy
Adderall is FDA-approved to treat ADHD and narcolepsy. It is available in both immediate-release (IR) and extended-release (XR) formulations.
- Adderall IR tablets are used for ADHD or narcolepsy in adults and children aged 3 years and older.
- Adderall XR capsules are approved for ADHD in adults and children aged 6 years and older.
Healthcare providers may also prescribe Adderall off-label for conditions such as fatigue, weight loss, and excessive daytime sleepiness related to other medical conditions. Its strength lies in its ability to enhance focus, attention, and reduce impulsivity and hyperactivity in individuals with ADHD, and to promote wakefulness in those with narcolepsy.
Phentermine: Appetite Suppression and Weight Loss
Phentermine is approved by the FDA for short-term use in conjunction with diet and exercise for weight loss in adults and adolescents aged 17 years and older. To be considered for phentermine, individuals typically need to have a body mass index (BMI) of 30 kg/m² or greater, or a BMI of 27 kg/m² or greater with at least one weight-related condition like hypertension, high cholesterol, or type 2 diabetes.
Phentermine’s strength is primarily in its appetite-suppressing effects. While it can have stimulant properties, it is not typically prescribed for ADHD as its impact on focus and attention is less pronounced compared to Adderall. However, some healthcare providers may use it off-label for ADHD in certain cases.
How They Work: Mechanisms of Action
Both Adderall and Phentermine exert their effects by influencing neurotransmitters in the brain, but they have slightly different primary mechanisms.
Adderall is composed of amphetamine and dextroamphetamine, which are believed to work by increasing the levels of norepinephrine and dopamine in the brain. These neurotransmitters play crucial roles in attention, focus, and impulse control. By increasing their availability, Adderall helps improve these functions in individuals with ADHD and promote wakefulness in narcolepsy.
Phentermine primarily works by stimulating the release of norepinephrine in the brain. Norepinephrine is involved in regulating appetite. By increasing norepinephrine levels, phentermine helps reduce hunger and increase feelings of fullness, thereby aiding in weight loss. While it also affects dopamine, its primary mechanism of action for weight loss is through appetite suppression via norepinephrine.
Dosage and Potency Considerations
Comparing the dosage of Phentermine and Adderall directly to determine “strength” can be misleading because they are used for different purposes and have different potencies in achieving their respective therapeutic effects.
Phentermine is typically prescribed in doses ranging from 15 mg to 37.5 mg taken once daily, usually in the morning. Lomaira, a brand of phentermine, comes in lower doses (8mg) and is taken up to three times daily before meals.
Adderall dosages vary depending on the condition being treated and the patient’s age. For ADHD, starting doses for Adderall IR can be as low as 2.5 mg daily in young children, gradually increasing to a maximum of 40 mg daily for adults and older children. Adderall XR typically starts at 10 mg once daily for children and adolescents and 20 mg once daily for adults. For narcolepsy, doses can range from 5 mg to 60 mg per day in divided doses.
In terms of potency as stimulants, Adderall is generally considered to have a more pronounced effect on focus and attention compared to phentermine. This is reflected in its Schedule II classification and its primary use for ADHD. Phentermine’s stimulant effect is more geared towards appetite suppression, and it is classified as Schedule IV, suggesting a comparatively lower potential for abuse and dependence related to its stimulant properties.
Side Effects: A Look at Potential Risks
Both Phentermine and Adderall can cause side effects, some of which are similar due to their stimulant nature, while others are more distinct.
Phentermine Side Effects
Common side effects of phentermine include:
- Dry mouth
- Unpleasant taste
- Stomach problems (vomiting, constipation, diarrhea)
Serious side effects, though less common, can include:
- Pulmonary hypertension
- Heart valve problems
- Increased heart rate and blood pressure
- Insomnia
- Restlessness
- Dizziness
Adderall Side Effects
Common side effects of Adderall include:
- Nervousness
- Headache
- Decreased appetite and weight loss
- Dry mouth
- Stomach problems (nausea, constipation, diarrhea)
- Insomnia
- Changes in sex drive
Serious side effects of Adderall can include:
- Cardiovascular problems (sudden death, heart attack, stroke in adults with pre-existing heart conditions)
- Psychiatric problems (psychosis, mania, hallucinations, aggression)
- Seizures
- Tics
- Numbness or weakness of limbs
- Slowed or difficult speech
Adderall carries a boxed warning from the FDA due to its high potential for abuse and risk of serious cardiovascular events and sudden death associated with misuse. While phentermine also has potential side effects, it does not carry a boxed warning, indicating a different level of risk profile compared to Adderall.
Safety and Precautions: Who Should Avoid Them?
Both Phentermine and Adderall have contraindications and precautions. They are not suitable for everyone, and it’s crucial to discuss your medical history and current medications with a healthcare provider before starting either drug.
Both medications are generally avoided in individuals with:
- History of heart disease (coronary artery disease, stroke, heart rhythm problems, congestive heart failure, hypertension)
- Taking or recently taken monoamine oxidase inhibitors (MAOIs)
- Overactive thyroid
- Glaucoma
- History of substance use disorder
- Pregnancy or breastfeeding
- Known allergies to the drug ingredients
Specific precautions for Phentermine include:
- Uncontrolled high blood pressure
- Pulmonary hypertension
Specific precautions for Adderall include:
- Pre-existing psychiatric conditions (bipolar disorder, psychosis)
- Seizure disorders
- Circulation problems in fingers and toes (Raynaud’s phenomenon)
Drug Interactions
Both medications can interact with other drugs. Potential interactions for Adderall include:
- MAOIs: Risk of hypertensive crisis, stroke, and other severe reactions.
- Serotonergic drugs: Increased risk of serotonin syndrome.
- Tricyclic antidepressants: Increased risk of cardiovascular side effects.
Potential interactions for Phentermine include:
- MAOIs: Risk of hypertensive crisis.
- Insulin: Phentermine may affect blood sugar levels.
- Alcohol: May increase cardiovascular side effects.
Summary
In the comparison of how strong is phentermine compared to adderall, it’s essential to recognize that “strength” is context-dependent. Adderall is generally considered a stronger stimulant in terms of its impact on focus, attention, and its higher potential for abuse and dependence, reflected in its Schedule II classification and boxed warning. Its primary strength is in treating ADHD and narcolepsy.
Phentermine is a stimulant primarily geared towards appetite suppression for weight loss and is classified as Schedule IV, indicating a lower potential for abuse compared to Adderall. Its strength lies in its effectiveness as an appetite suppressant for short-term weight management.
Ultimately, the “stronger” medication depends on the intended therapeutic goal. For ADHD and narcolepsy, Adderall is the more potent and appropriate choice. For weight loss due to appetite suppression, phentermine is specifically designed and approved. It is crucial to consult with a healthcare provider to determine which, if either, of these medications is appropriate based on individual health needs and conditions. They can provide personalized advice and weigh the benefits and risks of each medication in your specific situation.
