Two ingredients contained in nasal decongestants are to be more tightly controlled by the Medicines and Healthcare products Regulatory Agency (MHRA).
This follows a public consultation initiated by the MHRA due to increasing concern that pseudoephedrine and ephedrine may be extracted and used to illegally manufacture crystal meth.
The MHRA consultation ended on 29 July this year after considering views from industry, other organisations and public bodies.
It is recommended that large packs of pseudoephedrine and ephedrine will be replaced by smaller 720 mg packs, and customers will only be able to purchase one packet each.
Sales are also to be carried out by pharmacists only.
Dr. June Raine, director of vigilance and risk management of medicines at the MHRA, said "The MHRA is introducing these measures to protect the public health following concern that was highlighted during the consultation process.
"All stakeholders will be working together to ensure the controls are effective. The Expert Group will be carrying out a continuous programme to monitor the situation."