Investigating the Stimulant Effects: What Does DMHA Do to the Brain?

October 8, 2025 •

4 min read

Originally developed as a nasal decongestant in the 1950s, DMHA (Dimethylhexylamine) is a central nervous system stimulant that has re-emerged in pre-workout supplements [1.2.1, 1.2.4]. But what does DMHA do to the brain? It primarily increases the uptake of dopamine and noradrenaline [1.2.1].

Quick Summary

DMHA, or Octodrine, functions as a powerful central nervous system stimulant. It elevates levels of key neurotransmitters like dopamine and norepinephrine, leading to increased energy, focus, and a feeling of euphoria.

Key Points

Primary Action: DMHA is a central nervous system stimulant that primarily works by increasing the brain's levels of dopamine and norepinephrine [1.2.1].
Reported Effects: Users experience heightened energy, improved focus, mood elevation, and appetite suppression due to its neurochemical impact [1.2.4, 1.4.2].
Significant Risks: Side effects include increased heart rate, high blood pressure, and other cardiovascular issues similar to other potent stimulants [1.2.2, 1.5.1].
FDA Stance: The U.S. FDA considers dietary supplements containing DMHA to be adulterated and has classified it as an unsafe food additive [1.7.5, 1.8.2].
WADA Prohibition: The World Anti-Doping Agency (WADA) lists Octodrine (DMHA) as a stimulant prohibited for in-competition use [1.10.3, 1.10.5].
Comparison to DMAA: DMHA is structurally similar to the banned stimulant DMAA but is considered to be slightly less potent, around 80% of its strength [1.2.5].
Lack of Research: There is a significant lack of placebo-controlled human trials to verify the safety and efficacy of DMHA [1.3.1, 1.8.1].

What is DMHA?

DMHA, also known by names like Octodrine or 2-aminoisoheptane, is a synthetic stimulant compound [1.3.1]. It was first developed in the 1950s for use as a nasal decongestant to treat conditions like bronchitis and laryngitis due to its ability to constrict blood vessels [1.2.4, 1.10.5]. In recent years, it has been controversially included in dietary supplements, particularly those marketed for pre-workout energy, weight loss, and enhanced focus [1.2.4]. Structurally similar to the banned substance DMAA (1,3-dimethylamylamine), DMHA is often promoted as a 'safer' alternative, although this claim lacks robust scientific backing [1.5.1, 1.5.5]. The DMHA found in supplements is typically produced synthetically as it is less expensive than extracting it from natural sources like Juglans Regia (Walnut Bark) or Kigelia Africana [1.3.1, 1.5.1].

The Primary Mechanism: How DMHA Affects Neurotransmitters

The fundamental question, 'What does DMHA do to the brain?', can be answered by examining its impact on the central nervous system (CNS). DMHA is a sympathomimetic amine, meaning it mimics the effects of the body's natural sympathetic nervous system responses [1.3.4]. Its primary action is to increase the levels of two critical neurotransmitters: dopamine and norepinephrine [1.2.1].

It achieves this by temporarily preventing the reuptake of these chemicals into the presynaptic nerve [1.4.2]. By blocking their reabsorption, DMHA allows dopamine and norepinephrine to remain active in the synapse for a longer period. This amplified and prolonged activity is responsible for the substance's main effects [1.4.2].

Dopamine: Often called the "feel-good" neurotransmitter, dopamine is a key component of the brain's reward system. Elevated levels are associated with feelings of pleasure, motivation, and euphoria [1.2.3, 1.4.2]. This accounts for the mood-lifting properties reported by users.
Norepinephrine: This neurotransmitter is central to the 'fight-or-flight' response. Increased levels lead to heightened alertness, focus, energy, and an increased heart rate and blood pressure [1.2.1, 1.3.4]. This action underlies DMHA's reputation as a potent energy booster for workouts.

Some sources also suggest that DMHA has a methyl group that blocks the action of monoamine oxidase (MAO), an enzyme responsible for breaking down neurotransmitters like dopamine. This would further contribute to its stimulating effects and its reported half-life of around 9-11 hours [1.4.2].

Cognitive and Physical Effects

Due to its influence on dopamine and norepinephrine, users often seek DMHA for a range of perceived benefits:

Enhanced Energy and Focus: The most common reason for use, driven by the increase in norepinephrine, helping users push through intense physical activity [1.2.3, 1.2.4].
Mood Elevation and Euphoria: The dopaminergic effect can produce a significant mood lift and a sense of well-being [1.4.2].
Appetite Suppression: Like many stimulants, DMHA can reduce the desire to eat, making it an ingredient in some 'fat-burner' products [1.2.4, 1.4.2].
Increased Pain Threshold: Some studies noted that Octodrine could increase the pain threshold, which could be beneficial during strenuous exercise [1.3.1, 1.4.5].

Risks, Side Effects, and Legal Status

Despite its purported benefits, DMHA is associated with significant risks and a lack of long-term safety data [1.8.1]. The side effects are typical of potent CNS stimulants and can include:

Increased heart rate and high blood pressure [1.2.2, 1.2.5]
Shortness of breath [1.2.5]
Jitters, anxiety, and potential for energy crashes [1.4.2]
Serious cardiovascular events, as its effects are similar to other stimulants known to increase such risks [1.5.1, 1.6.2]

The U.S. Food and Drug Administration (FDA) has taken a clear stance, stating that DMHA is not a legitimate dietary ingredient and considers supplements containing it to be adulterated and unsafe for consumption [1.4.3, 1.7.5, 1.8.2]. It is also on the Department of Defense's Prohibited Dietary Supplement Ingredients list [1.4.5]. Furthermore, the World Anti-Doping Agency (WADA) prohibits Octodrine (DMHA) for in-competition use [1.10.3, 1.10.5].

DMHA vs. DMAA: A Comparison

DMHA is frequently compared to DMAA, its more notorious and widely banned predecessor. While they share a similar mechanism of action, there are key differences.


Feature	DMHA (Octodrine)	DMAA (Methylhexanamine)
Potency	Considered to be about 80% as potent as DMAA [1.2.5].	The more potent of the two, leading to more intense effects and side effects [1.2.5].
Structure	A structurally similar alkylamine, sometimes referred to as 1,5-dimethylhexylamine [1.5.3].	Also an alkylamine, known as 1,3-dimethylamylamine. It is structurally similar to amphetamine [1.5.3].
Legal Status	Considered an unsafe food additive by the FDA; supplements are adulterated [1.7.5]. Banned by WADA in-competition [1.10.3].	Banned by many governments and sporting bodies due to severe safety concerns, including links to heart attacks [1.5.1, 1.6.3].
Side Effects	Increased heart rate, high blood pressure, jitters. Assumed to have similar but potentially less severe risks than DMAA [1.2.2, 1.5.1].	Linked to cerebral hemorrhage, heart attacks, and death. Causes significant vasoconstriction and high blood pressure [1.6.1, 1.6.3, 1.8.3].

Conclusion

So, what does DMHA do to the brain? It acts as a powerful stimulant by increasing the activity of dopamine and norepinephrine, leading to enhanced energy, focus, and mood. However, these effects come with considerable risks, including cardiovascular strain and other adverse reactions common to strong stimulants. The lack of human clinical trials, combined with its classification by the FDA as an unsafe food additive and its ban by anti-doping agencies, underscores the serious safety concerns surrounding its use [1.3.1, 1.7.5, 1.10.5]. While often marketed as a high-performance aid, the evidence points to a compound with a risk profile that should not be taken lightly.

For more information on substances prohibited in sport, one authoritative source is the U.S. Anti-Doping Agency (USADA).

Frequently Asked Questions

No, the FDA has determined that DMHA is not a permissible ingredient in dietary supplements. The agency considers products containing DMHA to be adulterated and has issued warning letters to companies selling them [1.7.5, 1.8.4].

Common side effects include increased heart rate, high blood pressure, shortness of breath, and jitters [1.2.5]. Due to its stimulant nature, there are concerns it could lead to serious cardiovascular problems [1.6.2].

DMHA might cause a false positive on an initial urine screening test for amphetamines. However, it will not cause a positive result on a confirmation drug test, which is more specific [1.8.1].

Due to its ability to influence dopamine and norepinephrine, which play a role in cognitive functions, it is sometimes considered to have nootropic effects like enhanced focus and memory [1.4.2, 1.4.5].

Both are stimulants with similar structures. However, DMHA is considered about 80% as potent as DMAA. DMAA is more widely banned and associated with more severe health risks, including heart attacks and death [1.2.5, 1.6.3].

Yes. By preventing the reuptake of dopamine, DMHA can cause this neurotransmitter to remain active longer in the brain's reward system, leading to feelings of euphoria [1.4.2].

While a form of DMHA can be found in certain plants like the bark of the Juglans Regia tree, the version used in supplements is almost always synthetic because it is cheaper to produce [1.3.1, 1.5.1].