1 Hydralazine, Hydrochlorothiazide, Reserpine: A Summary

Brand name:

Ser- Ap- Es, Uni Serp, Diuretic Ap- Es, Hydrap- Es, Serpazide, Tri- Hydroserpine.

Ser- Ap- Es is an antihypertensive and diuretic drug, used to treat high blood pressure and retention of water in the body. This is a drug combination of hydralazine, hydrochlorothiazide and reserpine.

Hydralazine relaxes and widens the blood vessels to decrease the blood pressure and the force that the heart exerts to pump blood into the system.

Reserpine also relaxes the blood vessels and it makes the heart beat slower and easier by decreasing the level of a certain natural substance in the blood. Consequently, the blood pressure decreases.

Hydrochlorothiazide is a water pill or diuretic medication under the thiazide group. This helps the body excrete excess salt and water from the body through the urine to treat water retention/ edema and high blood pressure as well.


Read your medication guide and follow your doctor’s prescription at all times.

  • Take Ser- Ap- Es orally per doctor’s prescription. Take this drug with food or milk to prevent stomach upset.
  • The dosage depends on your medical condition or treatment response. Do not adjust your dose without your doctor’s recommendation.
  • Avoid alcohol intake and activities that require mental alertness (i.e. driving, operating machineries) because this medication can cause dizziness.
  • Likewise, get up slowly from sitting or lying position.
  • Avoid over exposure to sunlight and other artificial sources of ultraviolet rays (i.e. tanning booth) because Ser- Ap- Es can make you hypersensitive to sunlight. As much as possible, wear protective clothes (i.e. long sleeves) or apply sun screen when you are outdoors.
  • Continue using this medication on regular schedule (same time of the day). Do not stop taking this medication abruptly without consulting your doctor.

Inform your doctor immediately if your condition aggravates or does not improve.

Take your missed dose as soon as possible. However, make sure that the time interval between the missed and the next dose is not too close. Otherwise, stick with the regular schedule and leave out the missed dose. Do not double dose to cover up a missed dose. Record your missed dose and inform your doctor immediately if you missed several doses.


Ser- Ap- Es may interact with:

  • MAO inhibitor drugs (i.e. isocarboxazid, phenelzine, tranylcypromine)
  • Digoxin
  • Quinidine
  • Lithium
  • Antidepressant medications (i.e. amitriptyline, imipramine)
  • Medicine for diabetes (i.e. glipizide, glyburide)
  • Prednisone
  • Prednisolone
  • Other medications for hypertension/ high blood pressure, edema/ water retention, heart or prostate disorder
  • Sedatives
  • Analgesic or pain relievers
  • Anti- anxiety drugs and
  • Muscle relaxants

Some drugs may either lessen the beneficial effects or worsen the side effects of Ser- Ap- Es. Likewise, Ser- Ap- Es may make some drugs less efficient or intensify their side effects.

Make sure to inform your doctor about all other drugs you are currently taking or using (prescribed and non-prescribed medications including vitamins, minerals and herbal products) to check for possible drug interaction with Ser- Ap- Es.

Never alter the doses of other medications while on Ser- Ap- Es neither stop nor start any medicine without the doctor’s recommendation.

Side Effects:

There are no side effects known aside from a possible allergic reaction in people who have previous or unknown hypersensitivity to the drug.

Watch out for signs of allergic reactions such as:

  • Rash
  • Itching
  • Swelling


Before taking Ser- Ap- Es, tell your health care provider if you have/are:

  • Any allergies to any substance, food or medication, particularly to Ser- Ap- Es, hydralazine, hydrochlorothiazide or reserpine
  • Medical history or a present condition such as:

        o Heart disease (i.e. coronary heart disease, mitral valvular rheumatic heart disease

        o Stomach ulcers

        o Ulcerative colitis

        o Depression

        o Ongoing electroconvulsive shock therapy

        o MAO inhibitor intake in the past 14 days

        o Gallstones

        o Kidney problem

        o Liver disease

        o Diabetes

        o Gouty arthritis

        o Systemic lupus erythematosus

        o Pancreatitis

        o Asthma

        o Stroke

        o High blood cholesterol level

        o Pulmonary hypertension and

  • Pregnant, planning to get pregnant or currently breastfeeding a baby (It is not known if Ser- Ap- Es can harm the unborn child but it can pass through breast milk that may harm the nursing child. The risks and benefits of using this medication during pregnancy must be discussed well with your doctor.)