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Tizanidine
From PsychonautWiki Archive
Revision as of 22:10, 6 April 2022 by >Goornie(Added table)
WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.
DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.
Tizanidine (known by the trade names Zanaflex and Trinex among others) is a depressant substance of the imidazoline class. Tizanidine is primarily used primarily as an antispasmodic drug.
Tizanidine is a central α2 receptor agonist. The relationship between the α2 receptor agonism and the spasmolytic function of tizanidine is not fully understood.
Tizanidine is an imidazoline derivative and centrally acting α2 receptor agonist closely related to Clonidine. Tizanidine inhibits the release of excitatory amino acids from spinal interneurons. As a result, Tizanidine enhances the presynaptic inhibition of motor neurons.
Tizanidine also has some affinity for the α1 receptors, but to a lesser than Clonidine, which may explain why its cardiovascular effects are so much milder than that of Clonidine.
Tizanidine has also been found to have anticonvulsant effects against strychnine-induced seizures but not against GABA-induced seizures. The α2 receptor mediated inhibition of inter-neuronal activity appears to be the cause of Tizanidine's anti-convulsant properties.
Tizanidine has an oral bioavailability of 20-34% and an elimination half-life of 2.5 hours. It attains steady-state concentration within 24-48 hours after administration.
The table below compares the selectivity of Tizanidine and other drugs to the imidzaoline-receptor and the α2 receptors in rats. Tizanidine has a significantly greater selectivity to the imidazoline receptor than clonidine. The imidazoline receptor selectivity of tizanidine may be responsible for its unique pharmacological profile[1].
Drug
Imidazoline receptors Ki (nM)
α2 Receptors Ki (nM)
Tizanidine
4.17 ± 1.81
91.5 ± 9.1
Clonidine
9.20 ± 1.23
9.20 ± 1.23
Oxymethazoline
2.28 ± 0.36
25.9 ± 5.5
Naphazoline
309 ± 26
25.9 ± 5.5
Adrenaline
> 10000
3.18 ± 0.41
Subjective effects
Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), an open research literature based on anecdotal user reports and the personal analyses of PsychonautWikicontributors. As a result, they should be viewed with a healthy degree of skepticism.
It is also worth noting that these effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects. Likewise, adverse effects become increasingly likely with higher doses and may include addiction, severe injury, or death ☠.
Physical effects
Seizure suppression - Tizanidine has been found to suppress strycnine induced seizures, but not GABA induced seizures.
Sedation - Tizanidine can produce a strong sedative effect. Users can become very tired and sleep through stimuli that would otherwise wake them.
At high doses, geometry can be observed likely due to experiencing low blood pressure and circulation to the brain. The geometry is distinct from psychedelic and dissociative drugs. It can be described as intricate in complexity, abstract in form, synthetic in feel, unstructured in organization, dimly lit, multicolored in scheme, flat in shading, soft in edges, smooth in motion, slow in speed, small in size, angular in corners, non-immersive in depth, and consistent in intensity.
The geometry of Tizanidine never exceeds level 4. The doses required to observe such geometries can induce dangerously low blood pressures and cause one to lose consciousness. Users should exercise caution when taking hallucinogenic doses, as the threshold for hallucinations is not far from the threshold for psychosis in many users.
Hallucinatory states
In higher doses, Tizanidine is capable of inducing a delirious state.
Soreness - After the effects of tizanidine wear off, muscles that weren't sore before using the drug can become sore with more ease. For most users, this first presents itself as an increased soreness in the neck.
Experience reports
There are currently 0 experience reports which describe the effects of this substance in our experience index.
This toxicity and harm potential section is a stub.
As a result, it may contain incomplete or even dangerously wrong information! You can help by expanding upon or correcting it. Note: Always conduct independent research and use harm reduction practices if using this substance.
The LD50 of oral tizanidine in rats was found to be 414mg/kg in rats and 235 mg/kg in mice.
Tolerance and addiction potential
While dependence is rare, use of Tizanidine exceeding 36mg daily over an extended period of time can lead to hypertensive withdrawals. In cases where dependence has been built, a user should taper to avoid a hypertensive crisis.
Warning:Many psychoactive substances that are reasonably safe to use on their own can suddenly become dangerous and even life-threatening when combined with certain other substances. The following list provides some known dangerous interactions (although it is not guaranteed to include all of them).
Always conduct independent research (e.g. Google, DuckDuckGo, PubMed) to ensure that a combination of two or more substances is safe to consume. Some of the listed interactions have been sourced from TripSit.
↑S;, M. I. K. (n.d.). Tizanidine may discriminate between imidazoline-receptors and alpha 2-adrenoceptors. Japanese journal of pharmacology. Retrieved from https://pubmed.ncbi.nlm.nih.gov/1331591/
