Package Leaflet: Information for the User
Seguril 40 mg Tablets
Furosemide
Contents of the pack and other information:
Seguril 40 mg Tablets is a diuretic belonging to the group of sulfonamides. It acts by increasing urine elimination (diuretic) and reducing blood pressure (antihypertensive).
Always under the prescription of your doctor, this medicine is indicated for the treatment of:
Read carefully the instructions provided in section 3. "How to take Seguril".
Do not take Seguril
Consult your doctor or pharmacist before starting to take Seguril.
Be especially careful with this medicine:
During treatment with this medicine, periodic control of your blood levels of sodium, potassium, and creatinine will generally be required, especially if you suffer from severe fluid loss, due to vomiting, diarrhea, or intense sweating. Dehydration or hypovolemia, as well as any significant electrolyte and acid-base balance alterations, should be corrected. Treatment interruption may be required.
Elderly patients with dementia who are taking risperidone should be especially careful with the concomitant use of risperidone and furosemide. Risperidone is a medicine used to treat certain mental illnesses, such as dementia (a disease characterized by several symptoms: memory loss, speech problems, thinking problems).
Tell your doctor or pharmacist if you are taking, have recently taken, or might take any other medicines.
The effect of treatment may be affected if Seguril is used at the same time as other medicines.
Certain substances can increase their toxicity in the ear and kidneys if administered with this medicine. Therefore, they should only be administered together if there are medical reasons that require it.
These substances include:
Your doctor may need to change your dose and/or take other precautions if you are taking one of the following medicines:
The concomitant use of Seguril with other medicines can weaken the effect of these medicines, such as:
In other cases, concomitant use may increase the effects of these medicines, such as:
Certain anti-inflammatory and pain medicines (non-steroidal anti-inflammatory drugs, including acetylsalicylic acid) and epilepsy medicines (phenytoin) may reduce the effect of Seguril.
Furosemide may increase the toxicity of salicylates.
This medicine and sucralfate should not be administered together, with an interval of less than 2 hours, as the effect of Seguril may be reduced.
Medicines such as probenecid and methotrexate or other medicines that have significant renal elimination may reduce the effect of Seguril. In high-dose treatment, they may increase serum levels and increase the risk of adverse effects due to furosemide or concomitant administration.
The following substances can increase the risk of reducing potassium levels in the blood (hypokalemia) if administered with Seguril:
Certain electrolyte disturbances (for example, decreased potassium or magnesium levels in the blood) may increase the toxicity of certain medicines (for example, digitalis medicines and medicines that induce QT interval prolongation syndrome).
Patients undergoing treatment with Seguril and receiving high doses of certain cephalosporins (antibiotics) may suffer from a decrease in kidney function.
The concomitant administration of Seguril and cyclosporin A (a medicine used to prevent transplant rejection) is associated with an increased risk of gouty arthritis (joint inflammation) secondary to an increase in blood urea levels and kidney urea elimination problems.
Those patients at high risk of suffering from nephropathy (kidney disease) due to contrast media who receive Seguril are more likely to suffer from a deterioration of kidney function.
The administration of Seguril together with risperidone in elderly patients with dementia could increase mortality.
High doses of furosemide administered with levothyroxine may lead to a transient initial increase in free thyroid hormones, followed by a general decrease in total thyroid hormone levels.
Pregnancy, breastfeeding and fertility
If you are pregnant or breastfeeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.
If you are pregnant, you will only use Seguril if there are medical reasons that require it.
During breastfeeding, do not administer Seguril. If its administration is essential, your doctor may require you to interrupt breastfeeding, as furosemide passes into breast milk.
Driving and using machines
This medicine may cause dizziness or drowsiness. This can happen more often at the start of treatment, when your doctor increases the dose, or if you consume alcohol. Do not drive or use tools or machines if you feel dizzy or drowsy.
Certain side effects (e.g., an undesirable pronounced drop in blood pressure) can impair the ability to concentrate and react, and therefore constitute a risk in situations where these skills are especially important (e.g., operating vehicles or machinery).
Seguril 40 mg Tablets contains lactose
If your doctor has told you that you have an intolerance to certain sugars, consult with them before taking this medicine.
Follow exactly the administration instructions of this medicine indicated by your doctor or pharmacist. In case of doubt, consult your doctor or pharmacist again.
Remember to take your medicine.
Take Seguril on an empty stomach, swallowing it whole and with enough liquid.
If you think the action of this medicine is too strong or too weak, tell your doctor or pharmacist.
Your doctor will prescribe the lowest sufficient dose to produce the desired effect.
In adultsit is recommended to start treatment with half, one, or two tablets (20 to 80 mg of furosemide) daily. The maintenance dose is half to one tablet per day, and the maximum dose will be indicated by your doctor and will depend on your response to treatment.
Use in children
In infants and children, it is recommended to administer 2 mg/kg of body weight daily, up to a maximum of 40 mg per day.
Your doctor will indicate the duration of your treatment with this medicine. Do not stop treatment before.
If you take more Seguril than you should
In case of overdose or accidental ingestion, consult your doctor or go to the emergency department of the nearest hospital, accompanied by this leaflet, or call the Toxicology Information Service, telephone 91 562 04 20, indicating the medicine and the amount ingested.
An accidental overdose could lead to a severe drop in blood pressure (which can evolve into shock), kidney problems (acute renal failure), coagulation problems (thrombosis), delirium, paralysis affecting soft muscles (flaccid paralysis), apathy, and confusion.
No specific antidote is known.
In case of overdose, treatment will be based on symptoms.
If you forget to take Seguril
Do not take a double dose to make up for forgotten doses.
Like all medicines, this medicine can cause side effects, although not everybody gets them.
Side effects have been grouped by frequency:
Very common(may affect more than 1 in 10 people)
Common(may affect up to 1 in 10 people)
Uncommon(may affect up to 1 in 100 people)
Rare(may affect up to 1 in 1,000 people)
Very rare(may affect up to 1 in 10,000 people)
Frequency not known(cannot be estimated from the available data)
As with other diuretics, after prolonged administration of this medicine, there may be an increase in sodium, chloride, water, potassium, calcium, and magnesium elimination. These disturbances manifest with intense thirst, headache, confusion, muscle cramps, painful muscle contraction, especially in the limbs (tetany), muscle weakness, alterations in heart rhythm, and gastrointestinal symptoms.
Reporting of side effects
If you experience any side effects, talk to your doctor or pharmacist, even if it is possible side effects that are not listed in this leaflet. You can also report them directly through the Spanish Pharmacovigilance System for Human Use Medicines: https://www.notificaram.es. By reporting side effects, you can help provide more information on the safety of this medicine.
Keep this medicine out of sight and reach of children.
Store below 25°C.
Keep in the original packaging to protect it from light.
Do not use this medicine after the expiration date shown on the packaging after CAD. The expiration date is the last day of the month indicated.
Medicines should not be disposed of via wastewater or household waste. Deposit the packaging and any unused medicines at the SIGRE collection point in your pharmacy. If in doubt, ask your pharmacist how to dispose of the packaging and any unused medicines. This will help protect the environment.
Composition of Seguril 40 mg tablets
Appearance of the Product and Package Contents
Seguril 40 mg tablets are available in packages of 30 tablets.
They are round, white tablets, scored on one side and engraved with "DLI".
Marketing Authorization Holder and Manufacturer
Holder
sanofi-aventis, S.A.
C/ Rosselló i Porcel, 21
08016 Barcelona
Spain
Manufacturer
Famar Health Care Services Madrid, S.A.U.
Avda. de Leganés, 62
28923 Alcorcón (Madrid)
(Spain)
or
Opella Healthcare International SAS
56, Route de Choisy
60200 Compiègne
(France)
or
Sanofi S.r.l.
Strada Statale 17, Km 22
67019 Scoppito (L’Aquila)
Italy
Date of the Last Revision of this Leaflet: January 2024
Detailed information on this medicine is available on the website of the Spanish Agency for Medicines and Health Products (AEMPS) https://www.aemps.gob.es/
The average price of SEGURIL 40 mg TABLETS in October, 2025 is around 2.25 EUR. Prices may vary depending on the region, pharmacy, and whether a prescription is required. Always check with a local pharmacy or online source for the most accurate information.