If you've tried migraine treatment before, you may have encountered two names that come up repeatedly: sumatriptan and rizatriptan. Both belong to a group of medicines called triptans, both treat migraine attacks rather than preventing them, and both are available in the UK on prescription. But they're not identical. They differ in how quickly they work, what forms they come in, and how they interact with other medicines.
This guide compares sumatriptan and rizatriptan across the factors that matter most when choosing between them: onset of action, dosage, side effects, formulations, and the situations where one may be a better fit than the other.
What Are Sumatriptan and Rizatriptan?
Sumatriptan is the most widely prescribed triptan in the UK and has been licensed for migraine since 1991. It's available under the brand name Imigran, and 50mg tablets can be bought over the counter from pharmacies without a prescription, making it one of the few prescription-class migraine treatments with this status. Higher doses (100mg) and other formulations require a prescription.
Rizatriptan came later and is available as standard tablets and orodispersible tablets (sometimes called wafers or melts), which dissolve on the tongue without water. It's sold under the brand names Maxalt and Maxalt Melt. Unlike sumatriptan, rizatriptan is prescription-only across all doses and formulations.
Both medicines are indicated for the acute treatment of migraine attacks with or without aura in adults. Neither is licensed for migraine prevention; they're taken once a headache has started, not as a daily prophylactic.1,2
How Do They Work?
Sumatriptan and rizatriptan are both selective 5-HT1B/1D receptor agonists, a pharmacological label that describes exactly what they do. Serotonin (5-HT) receptors are found on the blood vessels around the brain and on the nerve endings of the trigeminal nerve, which is central to migraine pain.
During a migraine attack, blood vessels in the brain dilate and the trigeminal nerve releases inflammatory neuropeptides, including calcitonin gene-related peptide (CGRP). This combination drives the throbbing pain, nausea, and light sensitivity that characterise a migraine.
Both sumatriptan and rizatriptan work by binding to 5-HT1B receptors on cranial blood vessels, causing them to constrict, and to 5-HT1D receptors on trigeminal nerve endings, reducing the release of these pain-amplifying substances. The result is relief from headache pain, nausea, and sensitivity to light and sound.3
The mechanism is the same for both medicines. The practical differences come from their pharmacokinetics: specifically, how quickly each reaches effective concentrations in the bloodstream.
Sumatriptan vs Rizatriptan: Key Differences at a Glance
|
Sumatriptan |
Rizatriptan |
| Licensed dose (oral) |
50mg-100mg |
10mg (5mg if taking propranolol) |
| Time to peak plasma concentration |
~2 hours (oral tablet) |
~1-1.5 hours (oral tablet) |
| Bioavailability (oral) |
~14% |
~40-45% |
| Orodispersible formulation |
No (UK) |
Yes (wafer/melt) |
| Nasal spray |
Yes (10mg, 20mg) |
No |
| Subcutaneous injection |
Yes (6mg) |
No |
| OTC availability |
Yes (50mg tablets) |
No (prescription-only) |
| Max dose per 24 hours |
300mg (tablets) |
20mg |
| Caution with propranolol |
No dose adjustment needed |
Reduce to 5mg |
How Quickly Does Each Work?
Onset speed is the most clinically meaningful difference between the two medicines for most patients.
Rizatriptan reaches peak plasma concentration in approximately one to one and a half hours after an oral dose, and its higher oral bioavailability of around 40-45% means more of the active medicine reaches the circulation after a standard dose.4 Clinical studies have reported that meaningful pain relief can begin within 30 minutes of taking rizatriptan 10mg in some patients, with a significant proportion pain-free at one hour.
Sumatriptan has a lower oral bioavailability of around 14%, largely because it undergoes substantial first-pass metabolism in the liver and gut wall.4 Peak plasma levels from a standard 50mg oral tablet are reached at around two hours, though clinical response typically begins earlier, at around 30 to 60 minutes in most patients.5
In four randomised head-to-head clinical trials comparing oral formulations, rizatriptan 10mg showed a faster onset of pain relief than sumatriptan 50mg and 100mg, and a greater proportion of patients were pain-free at 60 and 120 minutes with rizatriptan.3
For migraines that build quickly or reach severe intensity fast, the speed advantage of rizatriptan may be the deciding factor. For attacks that develop more gradually, the difference in onset may be less important.
Dosage and How to Take Each Medicine
Sumatriptan dosage
The recommended starting dose of oral sumatriptan is 50mg, taken as early as possible after the headache begins. Some people find 100mg more effective; others respond well to 50mg. If the headache returns after initial relief, a second dose may be taken, but at least two hours must have passed since the first dose. The maximum total dose in any 24-hour period is 300mg.5
If a dose provides no relief at all, a second dose should not be taken for the same attack. Switch to a non-triptan painkiller such as paracetamol or ibuprofen instead.
Rizatriptan dosage
The standard dose of rizatriptan is 10mg. As with sumatriptan, it should be taken at the onset of the headache phase. If the headache returns after initial relief, a second 10mg dose may be taken, again with at least two hours between doses. The maximum in 24 hours is 20mg.2
A lower dose of 5mg is recommended for people also taking propranolol, a common migraine preventative and beta-blocker. Propranolol inhibits the enzyme that metabolises rizatriptan (MAO-A), which increases rizatriptan plasma concentrations, and the dose reduction manages this interaction.2
For both medicines, absorption is slower when taken with food, so it is generally preferable to take them on an empty stomach if possible.
Formulations: Tablets, Sprays, and Melts
Sumatriptan has the broader range of formulations available in the UK:
- Tablets (50mg, 100mg): the most commonly prescribed form
- Nasal spray (10mg, 20mg): useful if nausea prevents swallowing tablets; faster absorption than oral tablets but lower overall efficacy than the injection6
- Subcutaneous injection (6mg): the fastest-acting formulation, with meaningful relief typically within 10 minutes; generally reserved for severe or rapidly-peaking attacks6
Rizatriptan is available as:
- Standard tablets (5mg, 10mg): swallowed with water
- Orodispersible tablets (wafers or melts; 5mg, 10mg): dissolve on the tongue without water, which is useful if nausea makes swallowing difficult or if you're caught without a drink; absorption is comparable to the standard tablet
The orodispersible format is one of rizatriptan's practical advantages over sumatriptan tablets. It's easier to use at the onset of an attack and requires no liquid.
Side Effects
Sumatriptan and rizatriptan share a broadly similar side effect profile, as expected from medicines with the same mechanism of action. Common side effects reported with both include:1,2
- Sensations of tingling, warmth, heaviness, or pressure (particularly in the face, limbs, or chest)
- Flushing
- Dizziness or drowsiness
- Nausea
- Dry mouth
- Fatigue or weakness
A transient feeling of tightness or pressure in the chest or throat is a recognised effect of both triptans and can be alarming. It's usually brief and benign, but it can be difficult to distinguish from a cardiac symptom. If chest pain is severe, does not pass within a few minutes, or is accompanied by other symptoms such as pain radiating to the arm or jaw, stop taking the medication and seek urgent medical advice.1
Some comparative data suggest sumatriptan has a higher incidence of adverse events than some other triptans, including almotriptan.7 Individual responses vary considerably, though, and tolerability is partly personal.
Medication overuse headache is a risk with any acute migraine treatment, including both triptans. NICE defines medication overuse as taking triptans on 10 or more days per month; taking paracetamol or NSAIDs on 15 or more days per month also qualifies. Either pattern can cause a rebound headache cycle that becomes harder to treat. If you find yourself using triptans frequently, speak to your GP about preventative options.
Drug Interactions
Both medicines: ergotamine and other triptans
Neither sumatriptan nor rizatriptan should be taken with ergotamine-containing medicines or other triptans. Combining these increases the risk of coronary artery vasoconstriction. At least 24 hours must elapse after taking an ergotamine preparation before either triptan is given. After taking rizatriptan, wait at least six hours before taking any ergotamine-type medicine.1,2
Both medicines: MAOIs
Both sumatriptan and rizatriptan are contraindicated in people taking monoamine oxidase inhibitors (MAOIs). MAOIs inhibit the enzymes that break down triptans, increasing plasma concentrations and cardiovascular risk. The same caution applies for two weeks after stopping an MAOI.
Rizatriptan specifically: propranolol
Propranolol, widely used for migraine prevention, high blood pressure, and heart conditions, significantly increases rizatriptan plasma levels by inhibiting MAO-A metabolism. This is a clinically important interaction: the rizatriptan dose must be reduced to 5mg if you are also taking propranolol.2 Sumatriptan does not have this interaction.
Can you take paracetamol or ibuprofen with triptans?
Yes. Both sumatriptan and rizatriptan can be taken alongside paracetamol or NSAIDs such as ibuprofen. Combining a triptan with an NSAID may improve overall migraine relief, as the two classes of medicine target different aspects of the attack. Always read the patient information leaflet for both medicines before combining them.
Which Is Stronger: Sumatriptan or Rizatriptan?
Rizatriptan 10mg has demonstrated greater efficacy than sumatriptan 50mg in randomised head-to-head trials, with higher rates of pain freedom at two hours and a more rapid onset of action.3 Its substantially higher oral bioavailability (around 40-45% versus approximately 14% for sumatriptan) means proportionally more of the active dose reaches the circulation.4
That said, "stronger" isn't the same as "better for you." Individual response to triptans varies considerably. Some people who don't respond well to rizatriptan find sumatriptan effective, and vice versa. Migraine is also heterogeneous: attack severity, onset speed, and associated symptoms differ between individuals and between attacks. Formulation also matters: sumatriptan's subcutaneous injection reaches peak effect faster than any oral rizatriptan dose and is the most effective acute triptan formulation available.
NICE guidance recognises that if one triptan is ineffective or poorly tolerated, switching to an alternative triptan is appropriate.8 If you've tried sumatriptan without adequate relief, rizatriptan is a reasonable next option, and the reverse is equally true.
Which Should You Choose?
Neither medicine is universally superior. The right choice depends on your migraine pattern, other medicines you take, and how you prefer to take treatment.
Rizatriptan may suit you better if:
- Your migraines build quickly and you need relief as fast as possible
- You struggle to swallow tablets during an attack due to nausea (the orodispersible formulation dissolves without water)
- You're not taking propranolol and have no MAOI in your history
- Previous sumatriptan courses haven't provided satisfactory relief
Sumatriptan may suit you better if:
- You prefer the convenience of an OTC option for occasional use (50mg tablets, branded Imigran Recovery)
- You need the flexibility of multiple formulations: nasal spray if nausea is severe, or injection for very rapid-onset or severe attacks
- You're taking propranolol (no dose adjustment needed with sumatriptan)
- Rizatriptan hasn't worked adequately, or its side effects have been difficult
In practice, the most reliable way to find the right triptan is to try it during an actual attack, assess the response and tolerability, and discuss the outcome with your prescriber. Many people try more than one triptan before settling on a preferred option.
When to Seek Further Advice
Contact your GP or prescriber if you:
- Find that either medicine is not providing adequate relief after two or three attacks
- Experience chest pain or tightness that is severe, prolonged, or accompanied by other symptoms such as arm pain or breathlessness
- Are using acute migraine treatment on more than 10 to 15 days per month, as this may indicate medication overuse headache
- Have new symptoms alongside your headache (weakness on one side, speech difficulty, visual loss, or the worst headache of your life), as these require urgent medical review and may indicate something other than migraine
- Are pregnant or breastfeeding and need migraine relief; discuss safe options with your GP
Frequently Asked Questions
What is the difference between sumatriptan and rizatriptan?
Both are triptans used to treat migraine attacks, but they differ in how quickly they work, their available formulations, and some of their interactions. Rizatriptan has a higher oral bioavailability (around 40–45% versus approximately 14% for sumatriptan) and reaches peak plasma concentration faster, which can mean a quicker onset of relief. Sumatriptan has the broader range of formulations - tablets, nasal spray, and subcutaneous injection - and 50mg tablets are available over the counter as Imigran Recovery. Rizatriptan is prescription-only but comes as an orodispersible tablet (wafer/melt) that dissolves on the tongue without water.
Which works faster, sumatriptan or rizatriptan?
Rizatriptan generally reaches peak plasma concentration more quickly - within around one to one and a half hours of an oral dose compared to approximately two hours for sumatriptan tablets. In head-to-head clinical trials, a higher proportion of patients taking rizatriptan 10mg were pain-free at 60 and 120 minutes compared to those taking sumatriptan 50mg or 100mg. That said, sumatriptan's subcutaneous injection is the fastest-acting triptan formulation available and reaches peak effect within around 10 minutes - faster than any oral rizatriptan dose.
Can I take sumatriptan and rizatriptan together?
No. Taking two triptans at the same time or within 24 hours of each other is contraindicated due to the risk of coronary artery vasoconstriction. If one triptan doesn't work for a particular attack, switch to a non-triptan painkiller such as paracetamol or ibuprofen for that attack. You can use a different triptan for a subsequent attack, but always discuss switching with your prescriber first.
Can I take paracetamol or ibuprofen with sumatriptan or rizatriptan?
Yes. NICE guidance recommends taking a triptan together with either paracetamol or an NSAID such as ibuprofen as the first-line approach to treating a migraine attack - combination therapy is more effective than either medicine alone. Both sumatriptan and rizatriptan can be taken alongside either analgesic. Always read the patient information leaflet for both medicines before combining them.
Is rizatriptan stronger than sumatriptan?
In head-to-head clinical trials, rizatriptan 10mg showed greater efficacy than sumatriptan 50mg, with higher rates of pain freedom at two hours and a faster onset of action. However, individual responses to triptans vary considerably. Some people who don't respond well to rizatriptan find sumatriptan effective, and vice versa. If one triptan hasn't worked well for you, it's worth trying an alternative rather than assuming triptans as a class won't help.
Can I buy sumatriptan over the counter in the UK?
Yes, but only in the 50mg strength and in limited pack sizes. Sumatriptan 50mg is available as a pharmacy (P) medicine under the brand name Imigran Recovery. It can be purchased from a pharmacy without a prescription, but a pharmacist must approve the sale and will ask some questions to make sure it's suitable for you. The 100mg strength, nasal spray, and injection require a prescription, as does rizatriptan in all forms.
Can I take rizatriptan if I'm on propranolol?
A: Yes, but at a reduced dose. Propranolol significantly increases rizatriptan plasma concentrations by inhibiting the enzyme (MAO-A) that metabolises it. The recommended rizatriptan dose for anyone taking propranolol is 5mg rather than the standard 10mg, and you should allow at least two hours between doses of the two medicines. Sumatriptan does not have this interaction with propranolol and does not require a dose adjustment.
What should I do if sumatriptan stops working?
First, make sure you're taking it as early as possible after the headache phase begins. Triptans are generally more effective when taken promptly. If sumatriptan consistently provides inadequate relief, speak to your GP or prescriber. NICE guidance supports switching to a different triptan if the first is ineffective or poorly tolerated, so rizatriptan would be a reasonable alternative to try. A higher dose of sumatriptan (100mg instead of 50mg) may also be worth discussing.
How long after taking sumatriptan or rizatriptan can I take another dose?
For both medicines, you must wait at least two hours before taking a second dose. A second dose is only appropriate if you had initial relief and the headache then returned. If the first dose provided no relief at all, do not take a second dose for the same attack. The maximum daily dose is 300mg for sumatriptan tablets and 20mg for rizatriptan.
References
- Dr. Reddy's Laboratories (UK) Ltd. Sumatriptan 50mg film-coated Tablets — Summary of Product Characteristics. Electronic Medicines Compendium (eMC). medicines.org.uk/emc/product/3521/smpc
- Rizatriptan 10mg Tablets — Summary of Product Characteristics. Electronic Medicines Compendium (eMC). medicines.org.uk/emc/product/9893/smpc
- Tfelt-Hansen P, et al. Oral therapy for migraine: comparisons between rizatriptan and sumatriptan. A review of four randomized, double-blind clinical trials. Cephalalgia. 2000;20(10):887-893. PMID:11089515
- Tfelt-Hansen P, et al. Triptans in migraine: a comparative review of pharmacology, pharmacokinetics and efficacy. Drugs. 2000;60(6):1259-1287. PMID:11152011
- Imigran 50mg Tablets (sumatriptan) — Summary of Product Characteristics. Electronic Medicines Compendium (eMC). medicines.org.uk/emc/product/945/smpc
- Sumatriptan 50mg film-coated Tablets — Summary of Product Characteristics. Electronic Medicines Compendium (eMC). medicines.org.uk/emc/product/12390/smpc
- Mo Y, et al. Network meta-analysis of migraine disorder treatment by NSAIDs and triptans. Journal of Headache and Pain. 2016;17(1):113. doi:10.1186/s10194-016-0703-0
- National Institute for Health and Care Excellence (NICE). Headaches in over 12s: diagnosis and management. Clinical guideline CG150. Last updated June 2025. nice.org.uk/guidance/cg150
This article is intended for informational purposes only and does not replace professional medical advice. Always read the patient information leaflet supplied with your medication and speak to a healthcare professional if you have specific concerns.