Using rhinovirus type 15, they inoculated volunteers in the nose with both nasal drops and an aerosol (particle size 0.3 to 2.5 μm).

To apply the nasal drops, lie on a bed on your back with your head hanging over the edge.

To use the nasal drops, it is best to be lying down.

Another interferon alfa-2b medicine, "Grippferon", nasal drops, is used for treatment and emergency prevention of Influenza and cold.

To use the nasal drops, lie on your back with your head tilted back.

Endocrine deficiency often require lifelong supplement e.g. desmopressin for diabetes insipidus which can be applied as nasal drop.

Estrogen (Premarin) nasal drops or saturated potassium iodide have been used to induce edema of the eustachian tube opening.

Irrigation should be used with caution in infants, as nasal drops are not widely tolerated.

Ephedrine hydrochloride 1% nasal drops can relieve the painful swelling in the nasal passage and sinus on the affected side.

In Germany, nasal drops cost 1.5-2 times less than the same medicine costs in Lithuania.