Hydrochlorothiazide Side Effects, How it Works, Upsides & Downsides

Hydrochlorothiazide is an externally administered medication. It is sold under a number of brand names with Apo-hydro being one of the most common ones. This chemical substance is a thiazide diuretic medication, i.e., a water pill.


The medicine is used as a treatment for edema, i.e., fluid retention in patients with congestive heart failure, liver cirrhosis, and kidney disorders. It also treats edema caused by the intake of steroids or estrogen. It is also prescribed to treat hypertension, diabetes insipidus, and renal tubular acidosis. Its properties also make it useful to help reduce the risk of kidney stones in patients having a high level of calcium in the lungs.


Side effects of Hydrochlorothiazide

Hydrochlorothiazide, like other medicines, has some side effects as well. These range from mild to severe.

Some of the common side effects that are considered to be mild in nature are as follows:

  • Nausea and vomiting
  • Loss of appetite
  • Diarrhea
  • Constipation
  • Muscle spasms
  • Headaches
  • Dizziness


Most of these side effects tend to occur at the start of the treatment and perish within a day or two as it does not take long for the body to adjust and get accustomed to the presence of the medicine. However, they may persist and start to worsen, triggering serious medical conditions. Therefore, seek medical help promptly if any side effect is experienced.

Some of the potential side effects it may cause include:

  • Lightheadedness
  • Eye pain
  • Vision problems
  • Jaundice
  • Easy bruising and/or unusual bleeding through the nose, mouth, vagina, or rectum
  • Shortness of breath
  • Wheezing and coughing accompanied by foamy mucus
  • Chest pain
  • Signs of electrolyte imbalance, i.e., dry mouth, thirst, drowsiness, lack of energy, restlessness, muscle pain or weakness, fast heart rate, nausea and vomiting, little or no urine, etc.
  • Signs indicating a severe allergic reaction such as fever, sore throat, swollen face or tongue, eye burning sensation, skin pain accompanied by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Note that other side effects that have not been listed in this guide may also be experienced. Usually, doctors and pharmacists inform the patients about the side effects they are likely to experience at the start of their treatment.

For further queries regarding this, you may consult your doctor or pharmacist.

How to use?

Before starting your dose, you are strongly advised to read out the directions on the prescription label and follow them carefully.

The medicine is administered orally. It is usually prescribed once a day. However, your doctor may recommend otherwise, and you are required to follow the instructions of your doctor. Take timely and balanced doses; neither overdose nor skip.

Get frequent medical tests, and blood pressure checks. Keep a record of the results.



  • Neither use nor prescribe it to some without the recommendation of a doctor.
  • It may interact negatively with certain medicines. Therefore, for safety, give your doctor a list of all the medicines, if any, that you use to avoid inconvenience.
  • It is not prescribed under certain conditions. Therefore, it is essential to provide yours and your family’s medical history as a safety measure for further consideration at the start of your treatment.
  • If pregnant, or nursing a baby, inform your doctor immediately.
  • Keep it away from children’s reach, heat, and moisture.