The therapeutic effect is otherwise known as the "desired effect". The effect we want the drug to do. In contrast to Adverse or undesired effect.

The therapeutic dosage is the amount of a therapeutic agent which causes the therapeutic effect. This is prescribed by qualified therapists for varied conditions.

Non-therapeutic drug effects are those that don't treat the target condition. For instance, the stomach cramping caused by erythromycin is a non-therapeutic effect when erythromycin is used for infection; interestingly, it may be a therapeutic effect if erythromycin is used for gastroparesis.

Not a "cure" medicated to a "highly functional level"

It means generically feeling of wellbeing