People travel all the time and pack their bags with their essentials and also their medications. According to the mx.usembassy.gov it clearly states that Sudafed, Actifed, and even Vicks Inhalers can get you up to 3 years in a Mexican prison.
It seems like Mexico is taking the war on drugs seriously.
The reason is the common ingredient in those products in medicines that contain pseudoephedrine. The website states “It is illegal to bring into Mexico some over-the-counter medicines commonly used in the United States, including inhalers and some allergy and sinus medications. Specifically, products that contain stimulants (medicines that contain pseudoephedrine, such as Actifed, Sudafed, and Vicks inhalers) or codeine are prohibited”. Only recently women from Utah on route to a vacation in Puerto Vallarta, which included a trip to a Mexican jail after over-the-counter Sudafed pills that customs found in her luggage when they arrived at the Puerto Vallarta airport.
The reason for this is that the drug pseudoephedrine is one of the main ingredients that are used to make Meth. So beware, and share this and tell your friends, so that when they are traveling abroad, they check what they can or can’t bring into a foreign country. On the reverse side tourists entering the United States can also be jailed for carrying substances that are controlled here in the US, and face jail time as well. Check with site like this for answers on these subject just to make sure https://mx.usembassy.gov/information-regarding-bringing-medications-into-mexico/