Is Fentanyl legal in Mexico?

Legal status

Fentanyl is named in Mexican law, in article 234 of the Ley General de Salud, as a estupefaciente, a narcotic. The Act prints the entry as «FENTANIL and expressly listed fentanyl derivatives». That is the answer to whether Fentanyl is controlled: it is on the list the Act itself prints, and no inference from a treaty schedule or a chemical relative was needed to get there. The consolidated text used was the official Chamber of Deputies edition recording its latest reform as published in the Diario Oficial de la Federacion on 15 January 2026.

Consequences if caught

Article 479 gives Fentanyl no number at all, so the article 478 no-prosecution rule has nothing to measure and never applies to it, and unauthorised possession stays subject to the ordinary health and criminal provisions. Article 478 is a conditional no-prosecution rule and not a legal allowance. At or below the table amount, for strict immediate personal consumption and outside the protected places article 475 refers to, the prosecutor does not bring the article 477 case. Article 477 otherwise sets ten months to three years for non-commercial possession below one thousand times the table amount. Article 479 is not the controlled-substance list and is routinely misreported as one. It is a short table of eight maximum amounts used by articles 477 and 478 for strict, immediate personal consumption: opium two grams, heroin fifty milligrams, cannabis five grams, cocaine five hundred milligrams, LSD fifteen thousandths of a milligram, and MDA, MDMA and methamphetamine at forty milligrams or one tablet or capsule of not more than two hundred milligrams. Mexico has no death penalty for any offence, which article 22 of the Constitucion Politica de los Estados Unidos Mexicanos settles. The federal trafficking ceiling is twenty five years under article 194 of the Codigo Penal Federal, and the small-scale ceiling is eight years under article 475 of the Ley General de Salud.

If prescribed or medical

Narcotic; lawful medical possession requires the special prescription and authorised product. Personal import is not created by the schedule entry. Mexico controls narcotics prescribing through articles 240 onward, which impose special prescription and record-keeping duties, while article 245 applies group-specific controls to psychotropics. A foreign prescription evidences therapeutic purpose and does not create an article 479 allowance or override a prohibition.

Documentation

Carry the medicine in its original labelled packaging with the prescription and a medical letter in Spanish naming the patient, the active ingredient, the dose, the quantity and the treatment period. Those papers evidence therapeutic purpose and nothing more: they do not create an article 479 allowance and they do not override a prohibition. There is no article 479 figure for this substance, so there is no amount below which the prosecutor stands back. The article 234 entry for Fentanyl, a estupefaciente, a narcotic, was read in the official consolidated Ley General de Salud on 18 September 2026.

Drug laws and enforcement change and vary within a country. This is not legal advice. Always confirm with Mexico’s embassy or official drug authority before traveling; penalties can be severe, including imprisonment.