From the FDA Drug Label
The precise mechanism of action of baclofen is not fully known. Baclofen is capable of inhibiting both monosynaptic and polysynaptic reflexes at the spinal level, possibly by hyperpolarization of afferent terminals, although actions at supraspinal sites may also occur and contribute to its clinical effect Although baclofen is an analog of the putative inhibitory neurotransmitter gamma-aminobutyric acid (GABA), there is no conclusive evidence that actions on GABA systems are involved in the production of its clinical effects
The mechanism by which baclofen reduces hiccups in patients with intracranial hemorrhage is not specified in the drug label. The label does describe the general mechanism of action of baclofen, including its ability to inhibit reflexes at the spinal level, but it does not provide information on how this mechanism applies to the treatment of hiccups in patients with intracranial hemorrhage 1.
From the Research
Mechanism of Baclofen in Reducing Hiccups
- The exact mechanism by which baclofen reduces hiccups is not fully understood, but it is proposed that the mechanical aspects of hiccup are reduced by baclofen, leading to a perceptual blockage and a decrease in the reflex severity induced by the gamma-aminobutyric acid analogue 2.
- Baclofen, a GABA(B) receptor agonist, may reduce dopamine release by GABA(B) receptor stimulation, which is able to interrupt hiccup's reflex arc 3.
- The reduction of hiccup severity with baclofen may be due to its effect on the gamma-aminobutyric acid system, which plays a role in the regulation of the hiccup reflex 2.
Effectiveness of Baclofen in Treating Hiccups
- Baclofen has been shown to be effective in treating intractable hiccups in several studies, with a significant improvement in hiccup severity and a decrease in the frequency of hiccups 2, 4, 5.
- Baclofen has been used successfully in patients with chronic hiccup, with a long-term complete resolution or a considerable decrease in hiccups in a significant proportion of patients 5.
- Baclofen has also been used to treat persistent hiccup, with a rapid cessation of hiccups after a single administration of the drug 3.
Comparison with Other Treatments
- Baclofen is often used in practice for the treatment of hiccups, and has been shown to be effective in patients who have not responded to other treatments 4, 6.
- Chlorpromazine is the only drug registered for the treatment of persistent hiccups, but it has many side effects, and baclofen may be a useful alternative 6.