Rizatriptan: Effects, Uses & Risks

Rizatriptan is a drug of the triptans class of active ingredients. This stimulates the serotonin receptors and is used for moderate to severe forms of migraine. It not only relieves pain, but also has a positive effect on symptoms such as photosensitivity.

What is rizatriptan?

Rizatriptan is used to treat moderate to severe forms of migraine. The drug rizatriptan is a selective serotonin agonist used to treat cluster headaches and migraines. Selective serotonin agonists are pharmacological substances that can activate serotonin receptors. They thereby support tissue hormones and neurotransmitters. Rizatriptan belongs to the drug class of triptans, whose mechanism of action is generally based on the selective stimulation of serotonin receptors. The drug was approved in 1998 by the Food and Drug Administration (FDA) in the United States and by the Federal Institute for Drugs and Medical Devices in Germany as a prescription-only drug. Rizatriptan is prescribed for the treatment of migraine and cluster headaches. It not only has a positive effect on the pain condition, but also alleviates other symptoms such as photosensitivity and eye fibrillation. This is achieved by constricting the blood vessels in migraine headaches (vasoconstriction).

Pharmacologic action

Rizatriptan is an approved drug in the triptan class of drugs. Serotonin agonists are referred to as triptans. Serotonin agonists have an activating effect on the signal transmission of a cell’s receptors through their pharmacologic substance. In the case of rizatriptan, these are the 5-HT1D receptors. The stimulation of these receptors leads to a constriction of the intracranial (inside the skull) blood vessels. Furthermore, activated stimulus transmission from the receptors has an inhibitory effect on the release of vasoactive neuropeptides and inhibits central pain transmission in the brainstem. Neuropeptides are messenger substances in nervous tissue. The absorption of the drug rizatriptan is very fast compared to other triptans. Within about 50 minutes, the maximum active substance is distributed in the blood plasma. As a result, rizatriptan remains unchanged by about 45 percent in the systemic bloodstream and is only absorbed from the circulation after two to three hours (half-life). When the drug is taken orally, the effect occurs after only 30 minutes.

Medical use and application

Rizatriptan is indicated for severe headache and migraine attacks. Generally, this medication should be administered only to adults. It is taken during an acute attack and not as prophylactic therapy for headache and migraine. Rizatriptan is taken in the form of tablets or sublingual tablets. A sublingual tablet is a tablet that is placed under the tongue and dissolves there. This has the advantage that the active ingredient is absorbed directly through the mucous membranes and thus enters the bloodstream more quickly. The standard dosage of rizatriptan is about 10 milligrams; if liver or kidney function is impaired, only 5 milligrams should be prescribed. If the first symptoms of an impending migraine attack appear, an application should be taken immediately. Preliminary signs may include fatigue, sensitivity to light, or an aura. At these first signs, a single dose of 10 milligrams should be taken. If pain or other symptoms are still present after about 2 hours, a second application of 10 milligrams can be taken. However, the maximum daily dose of 20 milligrams should not be exceeded. About 10-20 percent of patients may not respond to rizatriptan. In this case, the treating physician should consider an alternative medication.

Risks and side effects

Compared with other drugs in this class, rizatriptan is reported to be well tolerated. The most common side effects may include nausea, dry mouth and thirst, flushing, fatigue, dizziness, muscle weakness, or generalized weakness. Occasionally, adverse side effects such as palpitations and shortness of breath may occur. Rarely occurring side effects, but which can be considered life-threatening, may include heart attack provocation and severe cardiac arrhythmias.In principle, rizatriptan should always be taken with consideration of the patient’s individual medical history. If there are pre-existing conditions such as high blood pressure, diabetes mellitus, peripheral vascular disease or liver and kidney dysfunction, taking the drug is associated with significantly increased risks. Women who are in menopause or smokers also belong to this risk group. The drug is absolutely contraindicated in angina pectoris and patients who have suffered a heart attack or stroke. Due to lack of studies, the drug Rizatriptan should not be prescribed to children, adolescents, adults over 65 years of age, pregnant women and nursing mothers. Taking different drugs of the same drug class and in combination with ergotamine derivatives uncontrollably increase the effect and increase the risk of side effects. Even when discontinuing such a pharmacological substance, there is always a potentially increased risk of serotonin syndrome. Serotonin syndrome manifests with symptoms such as general agitation, hallucinations, loss of coordination, increased heart rate, blood pressure fluctuations, increased reflexes, nausea, vomiting, diarrhea, and increased body temperature.