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Prazosin Side Effects

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Prazosin Side Effects, Dangers, & Risks Prazosin Shows Promise for Alcohol Use Disorder

What is Prazosin?

Prazosin (brand name is Minipress) is a prescription medication used to manage and treat hypertension, hyperplasia (increased cell production in normal tissue or organ), benign prostatic (prostate enlargement), PTSD-associated nightmares, and the Raynaud phenomenon. According to the National Institute of Health (NIH) [1], Prazosin is in a class of medications called alpha-blockers. It works by relaxing the blood vessels so that blood can flow more easily through the body. Prazosin comes only as a capsule you take by mouth.

Prazosin abuse has been a growing concern, it has been a prescription drug on the market for more than 20 years. Its use can cause uncomfortable Prazosin side effects, from lightheadedness and vomiting to fainting and depression. Although it may effectively treat symptoms associated with mental conditions such as PTSD, we are diving into its side effects and possible abuse. If enough of this prescription medication is taken, it can produce a psychotropic effect. That result is enough to cause users to exceed their dosage to chase the same effect. Tolerance and dependence can immediately decline into addiction when someone exhibits compulsive behaviors in seeking the drug. Prazosin is no different.

Can prazosin cause anxiety? Prazosin has an average rating of 7.0 out of 10 from 20 ratings for the treatment of Anxiety and Stress. 60% of reviewers reported a positive effect, while 25% reported an adverse effect. Does prazosin calm you down? Prazosin works in people with high blood pressure or heart failure by relaxing blood vessels.

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Prazosin Side Effects
One phenomenon associated with Prazosin is known as the “first dose response”, in which the Prazosin side effects – specifically orthostatic hypotension, dizziness, and drowsiness – are especially pronounced in the first dose.

Prazosin Side Effects

According to the National Center for Biotechnology Information (NCBI) [2], Prazosin may have effectively treated sleep problems related to post-traumatic stress disorder or PTSD. However, it’s still prescribed “off-label” for conditions. Off-label refers to drug use for conditions not approved by the U.S. Food and Drug Administration (FDA). 

Post-traumatic stress disorder (PTSD) is a psychiatric disorder with symptoms that include insomnia due to hyperarousal and recurring nightmares. PTSD is a severe anxiety disorder that impacts a large percentage of the US population, particularly veterans.

There have been reports that Prazosin, a commonly prescribed off-label drug, could be making suicidal thoughts worse for veterans suffering from PTSD [3]. A team of researchers from the Department of Veterans Affairs, seeking to collect more evidence, set out to study the sustained effectiveness of the treatment. They organized a large, lengthy, multisite trial—the most rigorous type of trial. Prazosin was no better than a placebo. According to The Department of Veterans Affairs (VA) [4], for nightmares associated with PTSD, there is insufficient evidence to recommend or against using Prazosin as mono- or augmentation therapy.

For Prazosin, off-label uses include an enlarged prostate, congestive heart failure, Raynaud’s disease, and PTSD-related sleep problems. Prazosin may not be as life-threatening as other drugs of abuse like benzodiazepines, opioids, heroin, cocaine, and meth, but this drug can still produce adverse side effects.

Prazosin side effects include:

  • Dizziness
  • Lightheadedness
  • Fainting
  • Fatigue
  • Low blood pressure
  • Headache
  • Rash
  • Hives
  • Itching
  • Rapid or irregular heartbeat
  • Difficulties breathing
  • Chest pains

How long do prazosin side effects last? Side effects usually go away after a few days. To lower side effects, it’s best to take the first dose (or the first higher dose) at bedtime.

Serious Prazosin Side Effects

Call your physician immediately if you experience adverse effects of prazosin. Adverse effects of prazosin and their symptoms can include the following:

  • Loss of consciousness (this can occur if you stand up too quickly after Sitting or lying down)
  • Very fast heartbeat
  • Depression
  • An erection lasting more than four hours
  • Swelling of your hands and feet
  • Difficulty breathing
  • Allergic reactions
  • Hives
  • Skin rash
  • Swelling of the lips, face, or tongue

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Prazosin Side Effects
Insomnia and hallucinations are listed as some of the rare Prazosin side effects by the manufacturer. This drug could be associated with rare psychiatric adverse effects and sleep disturbances.

Dangers of Recreational Prazosin Use

Prazosin use isn’t life-threatening in the way that more potent substances like stimulants and opioids are. However, the recreational use of this drug can be dangerous. It has the capacity to produce concerning Prazosin side effects.

Does prazosin make you sleepy? For one, upon first use, Prazosin can cause someone to experience lightheadedness, dizziness, and fainting if they get up too quickly from a lying-down position after taking the medication. Also, this drug can make the person drowsy to the point where operating machinery or driving a car becomes too dangerous.

Prazosin does not pose the addiction potential of sedative drugs such as Ambien, Restoril, and zaleplon (Sonata). However, if enough of this drug is used, it can produce a psychotropic effect. That result is enough to cause users to exceed their dosage to chase the effect that a previous dose produced.

How Much Prazosin is Fatal?

Can you overdose on Prazosin? Yes. An overdose of this prescription drug can happen when too much of it is ingested, which can happen intentionally or accidentally. Considering that Prazosin is not as potent or deadly as meth, an overdose is often the result of drug reactions.  Prazosin reacts badly with drugs like avanafil, sildenafil, tadalafil, vardenafil, and verapamil. 

Common prazosin overdose symptoms include:

  • Dizziness
  • Drowsiness
  • Lightheadedness
  • Decreased reflexes
  • Fainting

Like any similar product on the market, it also carries a risk of adverse effects and drug interactions. Also, patients with hypotension and other medical issues must consult an expert before taking it.  Most physicians also advise against drinking alcohol while taking any medications because it can inhibit its effectiveness. Patients are tempted to take more pills when this happens, increasing their risk of overdosing. Although the addictive nature of Prazosin is unknown, there are many other prescription drugs out there that are highly addictive. 

The high blood pressure drug prazosin is sometimes used to treat PTSD-related nightmares and insomnia that can increase suicide risk. But the study suggests the drug may worsen the side effects of prazosin for nightmares and may cause insomnia and not reduce suicidal thoughts in PTSD patients. We have to view this as not the final word, but it raises questions. The study included twenty PTSD patients, including two military veterans and several civilian women who had been sexually assaulted. All had active suicidal thoughts, some had previously attempted suicide, and most were taking antidepressants or had them prescribed for the study.

Risks of Using Prazosin

If someone is between the ages of 18 and 60, taking no other medication, or has no other medical conditions, risks and Prazosin side effects someone more likely to experience includes:

  • Drowsiness or dizziness, which is a common Prazosin side effects, may affect the person’s ability to operate or drive machinery, particularly within the first 24 hours of dosing when the dose is increased when going from a lying down to a standing position, during hot weather, after exercise, or after drinking alcohol. Do not drive or operate machinery until you know how this medication affects you.
  • A headache, weakness, lack of energy, nausea, and palpitations may be a Prazosin side effects .
  • Prazosin may rarely cause syncope (temporary loss of consciousness or fainting), particularly when going from a sitting or lying position to a standing position. These events may occur within 30 to 90 minutes of taking the drug. The risk of an episode is higher when prazosin is used in combination with another antihypertensive drug or during a dosage increase.
  • Sexual dysfunction is uncommon Prazosin side effects. Rarely, it may cause prolonged erections lasting more than four hours. Seek immediate medical help if these Prazosin side effects happen.
  • This drug may not be suitable for some people, including those with low blood pressure, pregnant or breastfeeding, or about to undergo eye surgery.
  • Effectiveness and safety in children have not been confirmed.
  • Prazosin may interact with other medications, which may cause adverse Prazosin side effects, including those that also lower blood pressure or cause dizziness.
  • Clinicians should be aware that there is a rare risk of priapism with prazosin, so, theoretically, there may be a greater than usual risk when combining trazodone and prazosin. Patients should be warned to pay attention to this possible Prazosin side effect.
  • Minipress (prazosin) lowers blood pressure but isn’t the first choice for treating high blood pressure (hypertension) due to Prazosin side effects.
  • Not preferred for older people due to more chance of prazosin side effects
  • The safety of prazosin in pregnant mothers has not been established. Only use if the potential benefit warrants the risk. Use caution if this drug is used in a breastfeeding woman.
Prazosin Side Effects
Prazosin is a well-tolerated medication with a small but positive evidence base for treating PTSD-associated nightmares. 

Prazosin Nightmares Side Effects

Nightmares, frequently associated with posttraumatic stress disorder and clinically relevant in today’s violence, are challenging to treat, with few pharmacologic options. Extremely distressing and disturbing, nightmares can have a profound negative effect on more than just an individual’s sleep; they also affect mental health, physical health, and quality of life.

These “repeated awakenings from the major sleep period or naps with detailed recall of extended and extremely frightening dreams, usually involving threats to survival, security, or self-esteem” are most frequently associated with posttraumatic stress disorder (PTSD) but can also be associated with other conditions. They can contribute to alcohol and substance abuse, suicidal ideation, or completed suicide.

With an increasing number of veterans of military deployments reintegrating into civilian life, physicians can expect to see more patients with symptoms of PTSD, including nightmares and reduced sleep quality. Prazosin has been studied off-label for the treatment of trauma-associated nightmares. Given the difficulty of treating nightmares, prazosin can be an important pharmacologic treatment option. Further clinical trials are recommended to expand our knowledge about prazosin in different patient populations.

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Prazosin Shows Promise for Alcohol Use Disorder

There are many reasons why someone drinks, and one of them is alcohol withdrawal. The withdrawal state causes anxiety, negative mood, and cravings, and these symptoms lead someone to turn to alcohol once more. More serious symptoms of alcohol withdrawal range from hallucinations about 12 to 24 hours after that last drink to seizures within the first two days after the person stops drinking. That isn’t the same as delirium tremens or DTs, as you’re likely to hear them called. DTs usually start 48 to 72 hours after you put down the glass. These are severe symptoms that include vivid hallucinations and delusions. 

Study results revealed that the α-1 adrenergic receptor antagonist prazosin might reduce the likelihood of heavy drinking and the number of drinks each week over time but not the number of drinking days per week. Therefore, these findings indicated that Prazosin shows potential as a harm-reduction pharmacologic treatment for alcohol use disorder rather than a full-abstinence approach.

Evidence suggests that elevated brain noradrenergic activity appears to be involved in initiating and maintaining alcohol use disorder. In human alcohol use disorder studies, Prazosin has been shown to reduce reactivity to stress and to result in reduced cravings, reduced drinks per week, and reduced drinking days per week.

According to the National Center for Biotechnology (NCBI) [5], There may be a benefit to introducing Prazosin during early drinking experiences. Prazosin slowed the acquisition of alcohol drinking and reduced the amount of alcohol consumed when administered before or concomitantly with the first opportunity to drink in rats genetically predisposed to high alcohol intake. 

Yale University [6] researchers report in the American Journal of Psychiatry has shown that stress centers of the brain are severely disrupted early in recovery, especially for those with alcohol withdrawal symptoms and high cravings, but that the disruption decreases the longer the person maintains sobriety. Prazosin could help bridge that gap by moderating cravings and withdrawal symptoms earlier in recovery and increasing the chances that alcoholics refrain from drinking.

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Who Has an Alcohol Use Disorder?

Problem drinking described as severe is given the medical diagnosis of “alcohol use disorder” or AUD. According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA) [7], an estimated 15 million individuals in the United States have AUD. 14.4 million adults in the United States ages 18 and older have an AUD, including 9.2 million men and 5.3 million women. AUD is a chronic relapsing addiction previously called alcoholism. AUD is characterized by an impaired ability to stop or control alcohol use despite adverse social, occupational, or health consequences.

Individuals must meet specific Diagnostic and Statistical Manual of Mental Disorders (DSM criteria) to be diagnosed with AUD. Using the DSM–5, anyone meeting any two of the 11 criteria during the same 12-month period receives an AUD diagnosis. The severity of AUD—mild, moderate, or severe—is based on the number of criteria met.

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We level Up NJ offers exceptional evidence-based recovery treatment programs. The combinations of therapies applied for each client are tailored to their individualized needs in treating drug dependency and alcohol abuse. We provide cutting-edge full-service rehabilitation care, including residential inpatient rehab, medically assisted detox, MAT for alcohol addiction, and co-occurring mental health therapy. Treatment services vary by facility. 

Prazosin may not be as life-threatening as other drugs of abuse, but this drug is still capable of producing adverse Prazosin side effects. The prescription drug detox process can be uncomfortable and difficult without medical assistance. However, getting through the detox process is crucial for continued treatment. We Level Up NJ provides proper care with round-the-clock medical staff to assist your recovery through our medically-assisted Detox Program. So, reclaim your life. Call us to speak with one of our treatment specialists. Our counselors know what you are going through and will answer any of your questions.

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[1] NIH –
[2] NCBI – https://www.ncbi.nlm.nih.govbooks/NBK555959/
[3] The Department of Veterans Affairs –
[4] NCBI –
[5] NIAAA –