Dimethocaine/Larocaine: Know more about it now
Dimethocaine, also known as DMC or larocaine, is a compound with a stimulatory effect. This effect resembles that of cocaine, although dimethocaine appears to be less potent. Just like cocaine, dimethocaine is addictive due to its stimulation of the reward pathway in the brain. However, dimethocaine is a legal cocaine replacement in some countries and is even listed by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) under the category “synthetic cocaine derivatives”. The structure of dimethocaine, being a 4-aminobenzoic acid ester, resembles that of procaine. It is found as a white powder at room temperature.
Dimethocaine was originally synthesized by the Hoffmann-La Roche company in 1930. It was sold under the market name larocaine. During the 1930s dimethocaine gained popularity in the US as a local anesthetic. Just like cocaine and procaine, it was used during surgery, primarily in dentistry, ophthalmology and otolaryngology. However, in the 1940s, it was removed from the market because of its psychoactive effects and risk of addiction. Nowadays dimethocaine is abused for these psychoactive effects. It is sold as a cocaine surrogate to circumvent legislation issues.
Basic Information & Chemical Properties
- Basic Information
|Synonyms:||Dimethocaine;NSC 68927;3-Diethylamino-2,2-dimethylpropyl 4-aminobenzoate;4-Aminobenzoic acid 3-(diethylamino)-2,2-dimethylpropyl ester;3-(Diethylamino)-2,2-dimethyl-1-propanol p-aminobenzoate;Larocaine;p-Aminobenzoic acid 3-(diethylamino)-2,2-dimethylpropyl;p-Aminobenzoic acid 3-(diethylamino)-2,2-dimethylpropyl ester|
|Product Categories:||chemical research;medicine grade;pharmaceutical intermediate;94-15-5|
- Chemical Properties
|Melting point||53.0 to 57.0 °C|
|Boiling point||421.21°C (rough estimate)|
|refractive index||1.5290 (estimate)|
|CAS DataBase Reference||94-15-5|
Dimethocaine Chemistry & Pharmacology
Dimethocaine has a structure that’s closer to procaine, a drug that lacks psychoactive effects, than cocaine. A major difference is that it lacks a tropane ring.
It functions as a dopamine reuptake inhibitor. Possible actions at other sites haven’t been examined.
The drug was only slightly less potent than cocaine for displacing mazindol at the dopamine transporter (DAT).
DA reuptake inhibition potency appears to go in this order: Cocaine > Dimethocaine > Tetracaine > Procaine > Chloroprocaine.
Dimethocaine elevated dopamine in the nucleus accumbens in rats. It’s also been shown to elevate dopamine levels in the striatum.
EC500 (concentration for 500% basal level) in striatum
Cocaine: 15 uM
Dimethocaine: 57 uM
Procaine: 3.5 mM
It’s been found to be 2-3x less potent than cocaine in some drug discrimination studies.
Dimethocaine fully substituted for cocaine when rats were trained to discriminate cocaine from saline. It also fully substituted when rats were trained to discriminate cocaine from procaine, further indicating cocaine-like effects.
Investigation of its pharmacokinetics in rats showed extensive metabolism. The most important phase 1 steps were hydroxylation and deethylation. The most important phase 2 steps were acetylation and glucuronidation.
In vitro tests found roles for CYP1A2, CYP2C19, CYP2D6, and CYP3A4. N-acetylation was carried out by NAT2, but not NAT1.
Dimethocaine Efficacy and side effects
Just like cocaine, dimethocaine inhibits the uptake of dopamine in the brain by interfering with the dopamine transporters. The potency of these drugs is linked to their affinity for the dopamine transporters, and their potency to inhibit dopamine uptake.
In studies with rhesus monkeys, the affinity of dimethocaine for dopamine transporters is smaller than that of cocaine, whereas dimethocaine’s potency to inhibit dopamine uptake is similar. This means that more of dimethocaine is needed to reach a similar response. The peak effects occurred within 10 to 20 minutes after the injection and decreased to baseline levels within an hour.
Dimethocaine is often abused as a legal substitute for cocaine. The drug is administered intravenously or nasally, because ingestion would lead to rapid hydrolyzation. Its positive effects are euphoria, stimulation, increased talkativeness and mood lift. However, because the drug acts similar as cocaine, it has comparable negative side effects. These side effects include: tachycardia, difficulty with breathing, pain on the chest, vasoconstriction, insomnia, paranoia and anxiety. Dimethocaine probably poses larger health issues than cocaine. This is due to the fact that more dimethocaine must be administered to produce the same euphoric feeling, resulting in a larger risk for the negative effects.
Cocaine and other local anaesthetics are known to produce cardiotoxicity by blocking sodium channels. However, no reports have been published of these same effects of cardiotoxicity associated with dimethocaine. There has been little research about toxicity of dimethocaine in humans, and therefore the exact lethal or pharmacological doses are unknown.
For mice, the dose at which acute toxicity occurs for intravenous administration is 40 mg/kg and for subcutaneous injection (injection in the layer of skin directly below the dermis and epidermis) this is 380 mg/kg. The lethal dose of dimethocaine for a mouse is 0.3 g per kilogram body weight.
An abdominal constriction test was performed in mice, using doses of 5, 10, and 20 mg/kg of dimethocaine which were administered subcutaneously. This test showed induced dose-dependent antinociceptive responses, which are processes that block detection of a painful or injurious stimulus by sensory neurons.
Impairment of memory processes was found to be a toxic effect in the elevated plus-maze test in mice.
Dimethocaine Legal Status
United States (as of February 2017)
- Controlled (list may not be complete)
Germany, Ireland, and Romania.
Ways to get Dimethocaine
AmarvelBio supplies Cas 94-15-5 Dimethocaine raw powder for lab research purposes. If you are interested in it, please browse the shop page to see more.
- “Dimethocaine – The Drug Classroom”. The Drug Classroom. Retrieved 2018-03-16.
- Meyer MR, Lindauer C, Maurer HH (February 2014). “Dimethocaine, a synthetic cocaine derivative: studies on its in vitro metabolism catalyzed by P450s and NAT2”. Toxicology Letters. 225 (1): 139–46.