Prestop 2.5mg XL Tablet 10s

NULL contains Prazosin, a quinazoline derivative that functions as a highly selective antagonist of postsynaptic alpha-1 adrenergic receptors. By blocking these receptors, Prazosin prevents the vasoconstrictive effects of naturally occurring stress hormones (like norepinephrine), leading to dilation of both arterioles and veins. This widespread vascular relaxation significantly decreases total peripheral resistance, which is the direct cause of its antihypertensive effect.

NULL is typically used as part of a combination regimen for essential hypertension, particularly when patients have not responded adequately to initial therapy with diuretics or beta-blockers. It offers sustained blood pressure control but requires cautious dosing, especially when initiating therapy, due to the prominent "first-dose effect", a risk of severe orthostatic hypotension (sudden drop in blood pressure upon standing).

In addition to hypertension, the muscle-relaxing effects of Prazosin are sometimes utilised for the off-label treatment of Benign Prostatic Hyperplasia (BPH) by relaxing the smooth muscle in the prostate and bladder neck, improving urinary flow. Its unique mechanism also makes it effective in reducing the frequency and intensity of trauma-related nightmares in patients with Post-Traumatic Stress Disorder (PTSD).

Effective blood pressure control with NULL helps to reduce the long-term risk of cardiovascular complications, including stroke, myocardial infarction, and heart failure. Regular medical follow-up, including blood pressure monitoring, is essential to ensure safe and effective use.

NULL is indicated for:

Essential Hypertension:

Used alone or in combination with other antihypertensive agents (e.g., diuretics or beta-blockers).

Off-Label Uses:

Treatment of symptoms associated with Benign Prostatic Hyperplasia (BPH).

Off-Label Uses:

Management of nightmares and sleep disturbances in patients with Post-Traumatic Stress Disorder (PTSD).

Effective Blood Pressure Reduction:

Provides sustained lowering of blood pressure by decreasing peripheral vascular resistance.

Dual Vascular Effects:

Dilates both peripheral arteries and veins, offering comprehensive relief of vascular tension.

Potential Symptom Relief:

Can improve urinary symptoms in men with BPH and reduce distress from PTSD-related nightmares.

Favourable Metabolic Profile:

Generally does not adversely affect glucose tolerance or lipid profiles.

When taken as directed, NULL is usually well-tolerated, but side effects are possible. The most significant concern is the "first-dose effect."

Common Side Effects:

• Dizziness or Lightheadedness (most common, especially orthostatic hypotension).

• Headache

• Drowsiness or Lethargy

• Weakness or Lack of Energy

• Palpitations (awareness of heartbeat)

• Nausea

Serious Side Effects (Stop taking the medicine and seek urgent medical attention if you experience):

• Severe Hypotension/Syncope (Fainting): This can happen, especially after the first dose or a dose increase, due to a severe drop in blood pressure upon standing (orthostatic hypotension).

• Priapism: A painful, prolonged erection unrelated to sexual activity (rare, but requires immediate medical attention).

• Severe Allergic Reaction: Rash, itching, swelling of the face, throat, or tongue, difficulty breathing.

• Severe Chest Pain or Irregular Heartbeat.

• Dosage: For hypertension, the initial dose is typically very low (e.g., 1mg) and is gradually increased by the physician to a maintenance dose of 5mg or higher, depending on the response. The 5mg tablet is a common maintenance dose.
• Administration: NULL 5mg Tablets should be swallowed whole, with or without food.
• First Dose Safety: To minimise the risk of the "first-dose effect" (severe dizziness/fainting from orthostatic hypotension), the first dose, and any dose increase, should be taken immediately before bedtime.
• Crucial Consistency: Do not stop or adjust the dosage without consulting your prescribing physician.

NULL lowers blood pressure by selectively blocking the alpha-1 adrenergic receptors located on the smooth muscle cells of blood vessels, including both arterioles and veins. Alpha-1 receptors are normally activated by the hormone norepinephrine, which causes the blood vessels to constrict (narrow). By blocking these receptors, the active ingredient Prazosin prevents norepinephrine from binding, leading to vasodilation (the relaxation and widening of the blood vessels). This widespread dilation reduces the overall resistance to blood flow in the peripheral circulation, known as Total Peripheral Resistance. The reduction in resistance lowers the pressure within the arteries, effectively treating hypertension and reducing the strain on the heart.

• First Dose Rule: Always take the first dose (and any increased dose) right before bed to help manage the risk of severe dizziness or fainting (the "first-dose effect").

• Stand Up Slowly: Get up slowly when rising from a sitting or lying position to minimise dizziness (orthostatic hypotension).

• Driving: Be extra cautious when driving or operating machinery until you know how the medication affects you.

• Monitoring: Your doctor will start you on a low dose and gradually increase it. Stick exactly to this titration schedule.

• Surgery: If you plan to have cataract surgery, tell your eye doctor that you are taking NULL.

Store the NULL Tablets in the original packaging at room temperature (typically between 20 °C and 25 °C / 68 °F and 77 °F), away from moisture, heat, and direct light. Keep the medication out of the reach of children.

• Food: The absorption of Prazosin is generally not affected by food, and NULL can be taken with or without meals.

• Other Antihypertensive Agents (e.g., Diuretics, Beta-Blockers): Co-administration may result in an additive hypotensive effect, requiring dose reduction of NULL or the other agents.

• Erectile Dysfunction (ED) Medications (e.g., Sildenafil, Tadalafil): NULL and ED drugs are both vasodilators, and combining them significantly increases the risk of severe hypotension. These combinations should be used with extreme caution and at lower doses.

• Alpha-Blockers (for BPH): Do not co-administer with other alpha-blockers (e.g., Tamsulosin, Alfuzosin) due to a highly increased risk of hypotension.

• Cataract Surgery (Intraoperative Floppy Iris Syndrome - IFIS): Prazosin and related alpha-1 blockers have been associated with IFIS during cataract surgery. Inform your eye surgeon that you are taking NULL prior to the procedure.

• Orthostatic Hypotension/Syncope History: Use with extreme caution in patients prone to low blood pressure or fainting.

• Congestive Heart Failure: Use with caution, as rapid blood pressure drops can be detrimental.

The maintenance dose of Prazosin is typically 5mg taken once, twice, or three times daily, as prescribed by the doctor.

The most likely manifestation of overdose is prolonged and severe hypotension (profoundly low blood pressure), often accompanied by dizziness, syncope (fainting), and shock. Action Required: If an overdose is suspected, immediately seek emergency medical assistance. Management typically involves supportive care, including lying the patient down and elevating the legs, and potentially IV fluid administration or vasopressors to counteract severe low blood pressure.

If you miss a dose, take it as soon as you remember, unless it is almost time for your next scheduled dose. If it is close to your next dose, skip the missed dose and resume your regular schedule. Do not take a double dose to make up for the missed one.