The unknown harms
What is still unknown about harm?
Ask about unknown harms and the medicines you already take.
As of September 2026, large or long studies had not properly established Selank’s safety.
FDA has an unanswered question
FDA’s warning about Selank says it lacks key information about harm when it is given to people.
For injections, FDA’s concern includes peptide particles sticking together and unwanted material related to the peptide in the medicine. These could cause an immune reaction.
An immune reaction means the body’s defence system may treat the substance as an invader.
This does not prove that any particular shot contains unwanted material.
Ask the pharmacy how it checks what is in the proposed shot.
Medicines and personal circumstances
It is not clear how taking Selank with calming medicines affects people.
The Russian leaflet says Selank can be combined with other medicines that act on the brain. But lab tests found that Selank could block some effects of two medicines, diazepam and olanzapine.
In rats, Selank with diazepam reduced anxiety more than either alone. These findings do not settle whether a combination helps or harms people.
Bring the names of medicines you take to the doctor. Ask about taking them together. Do not use this page as a plan to add or stop a medicine.
The leaflet excludes some groups
The Russian maker’s leaflet, checked in September 2026, excludes pregnancy, breastfeeding and people under 18 because those groups were not tested.
It also rules out use by someone who reacts badly to Selank.
These are details for nose drops, not an FDA-reviewed list of concerns for Selank injections.
Raise pregnancy, breastfeeding and any past reaction in the care discussion.
Severe symptoms need urgent help
MedlinePlus says to seek emergency care for signs of a severe allergy, including a swollen tongue or difficulty breathing.
If that is happening now, leave the reading for later.
Notes for this chapter
- FDA concerns about Selank
- Journal review of the limited evidence
- Lab work on combined drug actions
- Rat study of Selank with diazepam
- Russian nose-drop leaflet
The advice against use in certain people and the claims about combining medicines come from this leaflet.
- MedlinePlus on severe allergic reactions