Fosinopril and Hydrochlorothiazide (Oral)


Fosinopril and Hydrochlorothiazide is a drug combination used by patients looking to reduce hypertension (high blood pressure). Doing so is important as ongoing high blood pressure puts pressure on arteries and the heart by adding to their workload. If left untreated, hypertension can cause the heart and arteries to be unable to properly function. In turn, this can damage the blood vessels in the kidneys, brain and heart, leading to heart failure, kidney failure or strokes.

Ongoing high blood pressure can also lead to an increased risk of heart attacks. If properly controlled, patients can hopefully avoid such unwanted problems. The Hydrochlorothiazide element of this combination works by helping reduce the levels of water and salt in the body. It does this by helping the kidneys to increase the urine flow. At the same time, Fosinopril blocks a certain enzyme in your body which itself creates a substance that makes blood vessels become tighter. By doing this, blood vessels are able to relax.

Combined together, these two drugs have the effects of lowering blood pressure and increasing the supply of oxygen and blood to your heart. Do be aware that you cannot obtain the Fosinopril and Hydrochlorothiazide combination yourself, you will need a doctor's prescription. It has the ability to interact with a variety of different drugs and can cause a number of side effects to occur. As such, it is only suitable for certain patients.

Condition(s) treated

  • Hypertension

Type of medicine

  • Tablet

Side effects

As well as helping to treat hypertension, it is possible that this drug combination will cause other side effects to arise. In some cases, these side effects aren't very serious, but in other cases, they are more so. If you experience any of the side effects listed directly below then you should contact your doctor immediately.

Less common

  • Unusual weakness or tiredness

Other than these more worrying side effects, it is possible that the effects you experience are much less serious. Directly below are such side effects. It may be that they will pass as your treatment continues and your body adjusts to the medicine. However, if they are worrying you or are continuing for a long period of time, then you can still contact your doctor. They may be able to advise on ways to adjust your prescription in order to limit the effects you are experiencing.

More common

  • A cough

Less common

It may be that you experience other side effects not listed here. If that is the case, and if they are worrying you, then again, you can contact your doctor for advice.


Below you can find the typical doses of Fosinopril and Hydrochlorothiazide combination recommended to patients suffering from high blood pressure. Do be aware that your prescription may differ greatly from that below. This is because your doctor will have based your dosages on your exact medical circumstances, as well as any other drugs you are taking. You should never adjust how much you take unless told to do so by your doctor.

  • Adults. Take one or two tablets once per day.

It is important that you do not miss any scheduled doses, as this will impact the effectiveness of the treatment. If for some reason you do miss a dose, then you should take the missed dose as soon as you remember. However, if it is almost time for you to take your next scheduled dose, then you should skip the missed dose. It is important that you never double dose.

As well as prescribing you with Fosinopril and Hydrochlorothiazide combination, your doctor will likely also advise other lifestyle changes designed to lower your blood pressure. This may include eating fewer foods that are high in sodium. Your doctor will inform you of any such dietary changes that are best for your treatment. Before making any other changes to your diet, you should first discuss these with your doctor.

Even if you start to feel better, it is important that you continue to take your prescribed medicine, and maintain all scheduled appointments with your doctor. Many who suffer from high blood pressure are not even aware something is wrong as there may be no signs of any problem.

Instead of curing high blood pressure, this medicine is actually designed to help better control it. By stopping taking it, your blood pressure will easily rise back up again. In order to keep it down, you should follow your doctor's prescription. Do be aware that you may well need to take this medicine for the rest of your life in order to maintain a healthy lifestyle. Otherwise, you are at risk of having a stroke, experiencing heart failure, kidney disease or blood vessel disease.


It is also possible that the Fosinopril and Hydrochlorothiazide combination will interact with other drugs you are currently taking. Your doctor will, therefore, require you to inform them of all drugs you are currently taking. This includes prescription and non-prescription drugs, as well as any herbal or vitamin supplements. In some cases, an interaction should be avoided, and in others, it may be expected and necessary. Either way, your doctor is best placed to decide whether you should combine any two drugs at a given time. Directly below is a list of drugs with which it is not recommended you take at the same time as Fosinopril and Hydrochlorothiazide. As such, your doctor will likely need to alter either one or both of the drugs in order to avoid any interactions.

  • Dofetilide

Below is a list of drugs with which it is usually not recommended you take at the same time as Fosinopril and Hydrochlorothiazide. Your doctor may decide to limit the amount or frequency that you take either one or both of the medicines. Alternatively, they will prescribe different drugs altogether.

  • Phenylbutazone

If you take any of the following drugs at the same time as Fosinopril and Hydrochlorothiazide, then you are at a greater risk of experiencing certain side effects. However, it may well be necessary to take both at the same time. As such, your doctor may need to alter your intake of one or both medicines.

  • Lornoxicam

It is possible that this drug combination will interact with other aspects of your dietary intake, including what you eat, drink and smoke. Your doctor will advise you of any necessary dietary changes you should make. For example, you may need to reduce your intake of tobacco or alcohol.

Finally, other medical problems you suffer from could interact with Fosinopril and Hydrochlorothiazide. You should inform your doctor of all medical condition you have. In particular, make sure your doctor is aware of any of the following.

  • Kidney disease. Taking this medicine with this condition could cause blood pressure to fall too low


Before being able to prescribe this medicine, your doctor will need to weigh any increased risks you have against the benefits of using it. They will need to consult with you to understand the full extent of your medical condition. As a part of this, you should inform them of any allergies you have. This includes any allergies to foods, animals, dyes, and preservatives.

As of writing, no safety and efficacy standards have been established for the relationship between Fosinopril and Hydrochlorothiazide combination and pediatric patients. Your doctor can advise you if it is any less useful.

Any studies carried out on older patients using this drug combination have not identified any problems that would make it less useful for geriatric patients. However, older patients do tend to have more age-related heart or kidney problems. These will affect the dose needed to maintain effectiveness and safety.

As of writing, it is unclear as to heather appropriate studies have been carried out on the relationship between this drug and pregnant women in the first trimester. Your doctor will need to advise of any increased risks. However, studies have shown an increased risk to the fetus for women who are in the second or third trimester. Your doctor can advise on these risks and can weigh them against the benefits of taking the drug. If you become pregnant whilst using this drug combination, then you should inform your doctor immediately.

As of writing, there are no adequate studies that have been performed on breastfeeding women using this medicine. Yoru doctor is best placed to advise on any increased risks there may be.

Whilst treating this condition, your doctor will likely schedule regular appointments to track how your condition is progressing. They may need to take blood tests during these appointments. It is important you attend all appointments as your doctor can make any necessary adjustments to the prescribed medicines.

If you experience any of the following symptoms whilst using Fosinopril and Hydrochlorothiazide combination, you should contact your doctor immediately. They are symptoms of a condition known as angioedema.

  • Problems with breathing or swallowing

If you experience severe stomach pains whilst using this medicine, then you should contact your doctor immediately. This could be a sign of a problem known as intestinal angioedema.

During the first few days of using this medicine, you may experience a certain degree of lightheadedness. If this becomes more severe, and if you ever faint, then stop using it and inform your doctor.

If you experience symptoms of an infection, such as a sore throat, fever or chills, then inform your doctor immediately. This could be signs of an immune system condition known as neutropenia.

If you see no improvement in your condition within a few days of taking this medicine, or if your condition gets worse, tell your doctor.

Taking Fosinopril and Hydrochlorothiazide combination can potentially affect your blood sugar levels. If you notice changes in your urine or blood sugar test, then you can discuss this with your doctor. They can answer any questions you have.

If you are pregnant whilst using this drug, then you could inflict harm upon the unborn baby. You should tell your doctor right away if you become pregnant whilst taking this. You should look out for signs of jaundice (yellow eyes or skin), as this could mean you have contracted a serious liver condition.

Taking Fosinopril and Hydrochlorothiazide combination can lead to higher levels of potassium in your blood. You should first check with your doctor before taking any salt substitutes which contain potassium.

You may need to stop taking this medicine up to seven days prior to any medical tests or surgery as it could affect the results. Either way, inform your doctor or dentist before receiving any sort of treatment.


You should store your medicine in a sealed container and keep it at room temperature. Do not allow it to freeze, and do not expose it to heat, direct light or moisture. Once you finish your treatment, you should dispose of any remaining medicine in a safe and sensible manner as directed by your doctor. Similarly, if any medicine goes out of date at all, then you should dispose of it immediately. Finally, keep your medicine stored safely away from children.


If you are suffering from high blood pressure, then it is very important that you seek an appropriate form of treatment to help control the situation. Failure to do so can lead to a number of very serious medical problems, such as kidney failure or strokes. The Fosinopril and Hydrochlorothiazide combination is one form of treatment designed to help lower blood pressure levels by combatting two sources of the problem. You should familiarise yourself with the more serious side effects listed above. Be sure to inform your doctor immediately if you experience any of them.

Your doctor may well prescribe other changes you should make to your lifestyle so as to improve your condition. For the maximum health benefits possible, you should follow this guidance. For the first few days whilst using this medicine, you may experience lightheadedness, so you should not perform any dangerous tasks. You may wish to ask someone to help you drive to any necessary places in order to avoid the task yourself. This will allow you to see how the drug affects you.

If you wish to start taking any other drugs or have any other questions regarding this medication, you should address them to your doctor. They are best placed to understand the extent of your conditional and recommend any changes you should make to your treatment.