Please help with database design

[isdex1]

I would like to create a relationship between patient and allergen table. Each patient can have many allergies and each allergy can belongs to many patients.

Table tblPatient have primary key(PatientID) which is already link to a different table with a 1 to many relationship.

Please help. Thanks.

 

[Kanga35]

You may use one table for "Patient", one table for "allergen" and one table linking both and containing 2 columns, the recordID of patient and the allergenID.
That table can then be filtered by PatientID (to find all allergies of a given patient) or allergenID (to find all the patient having a given allergie.