Ibudilast (development codes: AV-411 or MN-166) is an anti-inflammatory drug used mainly in Japan, which acts as a phosphodiesterase inhibitor, inhibiting the PDE4 subtype to the greatest extent,[1] but also showing significant inhibition of other PDE subtypes.

[4] Ibudilast ophthalmic solution is indicated for the treatment of allergic conjunctivitis and hay fever.

Ibudilast has bronchodilator, vasodilator[10] and neuroprotective effects,[11][12] and is mainly used in the treatment of asthma and stroke.

This activity has been shown to make ibudilast useful in the treatment of neuropathic pain and it not only enhances analgesia produced by opioid drugs, but also reduces the development of tolerance.

[20] TLR4 antagonists theoretically reverse the increase in pain and inflammation caused by most TLR4 agonists, which includes alcohol & many opiate or opioid drugs.