Cazosin

Cazosin is an oral blood pressure medication containing Doxazosin 2 mg as its active ingredient. It belongs to the Alpha-1 Adrenergic Blocker drug class and is manufactured by Millimed in Thailand.

Doxazosin works by blocking Alpha-1 adrenergic receptors on smooth muscles of blood vessels and the prostate gland. This causes blood vessels to relax, improving blood flow and reducing blood pressure, while also relaxing muscles at the bladder neck and prostate to improve urinary flow.

Cazosin is an immediate-release formulation with a half-life of approximately 22 hours, allowing once-daily dosing. A bioequivalence study comparing Cazosin to Cardura (the originator brand by Pfizer) in healthy Thai volunteers confirmed equivalent efficacy.

Hypertension (High Blood Pressure): Cazosin helps reduce both systolic and diastolic blood pressure. It is used as add-on therapy with other blood pressure medications, particularly for resistant hypertension. The ASCOT study found that Doxazosin, used as a third-line agent, reduced blood pressure by an average of 12/7 mmHg.

Benign Prostatic Hyperplasia (BPH): Relieves urinary symptoms including difficulty urinating, frequent urination (especially at night), weak urine stream, and incomplete bladder emptying. It improves urine flow rate. However, Doxazosin does not shrink the prostate.

Dual benefit for men with both conditions: Cazosin is one of the few blood pressure medications that treats both hypertension and BPH symptoms simultaneously, reducing the total number of medications needed.

Starting dose: Take 1 mg once daily, preferably at bedtime. Your doctor will gradually increase the dose every 1–2 weeks based on response.

Maintenance dose:

• Hypertension — increase to 2–4 mg once daily, maximum 16 mg/day
• BPH — increase to 2–4 mg once daily, maximum 8 mg/day

Elderly patients: Start at the lowest dose (0.5–1 mg) and titrate cautiously due to higher risk of orthostatic hypotension.

If you miss a dose: Skip the missed dose and take the next one at the usual time. Never take a double dose. If you have missed several days, restart at a low dose to prevent dizziness.

Important: Can be taken with or without food. Take at the same time each day.

Common side effects:

• Dizziness, lightheadedness — the most frequent side effect, especially when first starting or increasing the dose
• Headache, fatigue, drowsiness
• Swelling of ankles and feet (peripheral oedema)
• Nausea, abdominal pain
• Runny nose, nasal congestion

Serious side effects (stop taking and seek medical attention):

• Fainting upon standing (orthostatic hypotension) — especially after the first dose or dose increase
• Rapid heartbeat, chest pain
• Severe allergic reaction: rash, hives, swelling of face/lips/throat, difficulty breathing
• Severe swelling (may indicate heart failure)

Do not use:

• Allergy to Doxazosin or other quinazoline derivatives (e.g., Prazosin, Terazosin)
• Severe liver disease
• History of orthostatic hypotension

Use with caution:

• Heart disease — especially heart failure; use with caution
• Planned cataract surgery — inform your ophthalmologist, as Doxazosin may cause Intraoperative Floppy Iris Syndrome (IFIS)
• Pregnancy and breastfeeding — insufficient safety data; consult doctor
• Elderly patients — higher risk of fainting; stand up slowly
• Avoid alcohol during treatment as it may worsen dizziness
• Do not drive or operate machinery for 24 hours after starting or increasing the dose

Cazosin vs. Cardura XL: Same active ingredient (Doxazosin). Cazosin is a generic by Millimed in Immediate Release at a more accessible price. Cardura XL is the originator brand by Pfizer in Extended Release at a higher price. Both have equivalent efficacy confirmed by a bioequivalence study.

Cazosin vs. Terazosin: Both are alpha-blockers for hypertension and BPH. Terazosin has a shorter half-life (~12 hours) while Doxazosin's is longer (~22 hours), providing more consistent effect.

Cazosin vs. Tamsulosin: Tamsulosin is more selective for Alpha-1A receptors, primarily for BPH with less blood pressure-lowering effect. Cazosin treats both conditions, ideal for patients with both hypertension and BPH.

Medications requiring special caution:

• PDE-5 Inhibitors (Viagra, Cialis, Sidegra) — Do not combine without medical advice; may cause dangerously low blood pressure. Separate doses by at least 4 hours.
• Other blood pressure medications — Can be used together but risk of hypotension; doctor will adjust dosages.
• NSAIDs (Ibuprofen, Diclofenac) — May reduce the blood pressure-lowering effect of Doxazosin.
• Clarithromycin, Ketoconazole — These CYP3A4 inhibitors increase Doxazosin blood levels.

Other alpha-blockers (e.g., Tamsulosin) — Do not combine; significantly increases the risk of severe hypotension.

Doxazosin has a half-life of approximately 22 hours, allowing once-daily dosing. Peak blood levels are reached within 2–3 hours after taking (faster than XL formula as it is Immediate Release).

For hypertension: Blood pressure reduction typically begins within 1–2 weeks, but may take 4–6 weeks for full effect.

For BPH: Urinary symptoms usually start improving within 1–2 weeks, but up to 4 weeks may be needed for noticeable improvement.

If symptoms haven't improved after 4 weeks, consult your doctor about dose adjustment or alternative treatment.

Cazosin is a pharmacist-dispensed medication. You can order online from Intimo Life.

Can I buy Cazosin online?

Yes. Order through Intimo Life — select the product, consult with a licensed pharmacist online, and receive your medication at home.

Do I need a prescription?

A doctor's prescription is not required, but the medication must be dispensed by a licensed pharmacist. At Intimo Life, our pharmacist will review your symptoms and health history to confirm suitability before shipping.

How does Intimo Life ship orders?

We deliver nationwide in Thailand with discreet packaging — no product names on the outside.