What is it:

Diphenhydramine, known by its brand name Benadryl, is an OTC medication used to treat allergies, motion sickness, and insomnia.¹ Classified as an antihistamine, it is also recommended by doctors to treat anxiety, although there are no studies to support this indication. It comes in 25mg tablets.

(Learn more from the NIH U.S. National Library of Medicine)

What it does:

Diphenhydramine blocks the action of histamine, which is the cause of allergic symptoms.¹ The mechanism of action for anxiety is unknown, although the sedation and sleep induction properties are most likely what helps for anxiety.

Considerations:

Diphenhydramine has the potential for multiple side effects, including dry mouth/nose/throat, sedation, dizziness, nausea/vomiting, headache, loss of appetite, constipation, increased chest congestion, muscle weakness, anxiety, and excitement (especially in children). Some serious, yet uncommon side effects include vision problems and problems with urination.¹

Dosage

The optimal dose is 25mg to 50mg on an as needed basis for anxiety, not to exceed 200mg in 24 hours.

Other names:

Aler-Dryl, Nytol, PediaCare Children’s Allergy, Siladryl, Silphen, Sominex, Unisom

What is it:

Melatonin is a natural hormone that our bodies make to induce sleep. It is used for insomnia and anxiety, and classified as a dietary supplement.^1-2 Also classified as an OTC medication, it comes in 1mg, 3mg, 5mg, and 10mg tablets. It also comes in various other unmarked dosages from various manufacturers.

(Learn more from the NIH U.S. National Library of Medicine)

What it does:

Melatonin modulates GABA, and protects against anxiety induced by sleep deprivation.³

Dosage

The optimal dose is 3mg to 6mg daily.¹

Considerations:

Melatonin has the potential for a few side effects, including sedation, headache, depression, dizziness, stomach pain, and irritability.²

Other names:

N-acetyl-5-methoxytryptamine, pineal hormone