What causes phentermine headaches and how can you solve them? Discover the potential reasons behind phentermine-induced headaches and effective strategies to manage this common side effect.

Understanding Phentermine Headaches

Phentermine, a popular weight-loss medication, is known to cause a variety of side effects, with headaches being one of the most common. Around half of all individuals who take phentermine report experiencing headaches. The causes of these headaches can be attributed to the medication itself or related lifestyle changes, and even mild phentermine headaches can significantly impact an individual’s quality of life.

Factors Influencing Phentermine Headaches

New Users

Headaches and other side effects are most prevalent when first starting phentermine. This is due to the body’s adjustments to the effects of the medication. Individuals who are particularly sensitive to the active ingredients in phentermine may be more likely to experience headaches as their body adapts to the treatment.

Drinkers and Smokers

Lifestyle changes can also affect the likelihood of developing phentermine-induced headaches. Those who smoke, consume alcohol, or drink coffee are at a higher risk of experiencing headaches. Doctors often encourage phentermine users to avoid these habits while taking the medication, as the combination of substances can lead to problematic and potentially dangerous results.

Causes of Phentermine Headaches

Stimulant Effect

The primary reason phentermine causes headaches is its stimulating effects. Phentermine works as a sympathetic amine, mimicking the “fight or flight” response, which can lead to vasoconstriction (narrowing of blood vessels) and vasodilation (expansion of blood vessels). These cardiovascular effects can contribute to the development of headaches, similar to the way excessive caffeine intake can cause headaches.

Dehydration

Phentermine can also lead to dehydration, which is a common trigger for headaches. The medication’s stimulant properties can cause increased urination and fluid loss, leading to dehydration and the onset of headaches.

Caffeine Withdrawal

Some individuals may experience headaches due to caffeine withdrawal when they start taking phentermine. If they were previously relying on caffeine to suppress their appetite, the sudden lack of caffeine can result in withdrawal symptoms, including headaches.

Managing Phentermine Headaches

Hydration and Electrolyte Replenishment

To alleviate phentermine-induced headaches, it is important to stay hydrated and replenish electrolytes. Drinking plenty of water and consuming electrolyte-rich foods or supplements can help counteract the dehydrating effects of the medication.

Reducing Stimulant Intake

Avoiding other stimulants, such as caffeine, while taking phentermine can help reduce the risk of headaches. Limiting or eliminating the use of coffee, energy drinks, or other stimulants can help minimize the combined stimulant effects and prevent headaches.

Lifestyle Modifications

Making lifestyle changes, such as quitting smoking and reducing alcohol consumption, can also help mitigate the risk of phentermine-induced headaches. Adhering to a healthier lifestyle can improve the overall effectiveness of the medication and reduce the likelihood of experiencing side effects.

Seeking Medical Advice

If the headaches become severe or persistent, it is important to consult a healthcare provider. They may adjust the dosage or change the medication schedule to better manage the side effects. In some cases, they may recommend alternative weight-loss strategies if the headaches cannot be effectively controlled.

Conclusion

Phentermine-induced headaches are a common side effect of this weight-loss medication, but they can be effectively managed through various strategies. Understanding the potential causes, such as the stimulant effects, dehydration, and caffeine withdrawal, and implementing appropriate measures like hydration, reducing stimulant intake, and lifestyle modifications, can help individuals find relief and optimize the benefits of phentermine treatment.

What Causes Phentermine Headache, and What you can Do to Solve It

Phentermine is known to cause a few side effects. Of these, headaches are the most common. Around half of all people who take phentermine report having headaches. What causes it and what you can do to get rid of a phentermine headache? 

The phentermine headache could be caused by either the pill itself or the related lifestyle changes, but even mild phentermine headaches can have a major impact on your overall quality of life. That’s why we put together this guide of the potential causes of phentermine headache and what you can do about the problem.

Please note, mild headaches are one of the most common phentermine side effects. If your headache could be considered severe or it doesn’t go away then you should consult a doctor. The pain could be a symptom of a more serious problem.

Who Gets Phentermine Headaches?

While it’s true that not everyone who takes phentermine will experience headaches, it does remain one of the more common reactions to the medication. New users and users that take medication alongside phentermine will be more likely to develop headaches, along with other side effects.

New Users

Headaches – and other side effects – are most common when first taking phentermine. This is due to your body taking time to adjust to the effects of phentermine. As is the case with every chemical substance, different people react differently to the active ingredients in phentermine. If you are particularly sensitive, headaches can occur as your body adjusts to the medication.

Regardless, you should consider talking to your doctor if the headaches become more severe or last for more than a few days. They may wish to decrease your phentermine dose or change your schedule. Making a change like this could reduce phentermine side effects and help you to better enjoy the benefits of taking phentermine.

Phentermine is still effective on a smaller dose, so don’t worry too much that the phentermine won’t work properly. Even so, you should never adjust your dosage or schedule without having first consulted your doctor.

Drinkers and Smokers

Lifestyle changes could also affect your chances of developing headaches with phentermine. Due to how different substances interact with each other, those who smoke, drink alcohol, or drink coffee are more at risk of developing headaches. This increased risk of developing side effects is why doctors encourage phentermine users to give up these habits while using the medication.

Alcohol and phentermine should never be mixed. The combination has been shown to produce problematic, if not potentially dangerous, results. Alcohol will react with phentermine and increase sleepiness, dizziness, and the stress on organs. It also contributes to an increase in blood pressure. Be sure to avoid drinking alcohol while taking phentermine.

Nicotine and caffeine are stimulants by nature. It is advised that you avoid using any kind of stimulant while taking phentermine given that phentermine itself is a potent stimulant. Users that combine phentermine with other stimulants are at a greater risk of developing negative side effects, including headaches.

What Causes Phentermine Headaches?

There are several different reasons that phentermine headaches may occur. It can be difficult to identify the particular cause of your headache. Therefore it helps to know about the different potential causes. Below are some of the most common causes of phentermine headaches, both related to phentermine itself and to outside lifestyle factors.

Taking Stimulants

The main reason that phentermine causes headaches is the stimulating effects. Phentermine works as a sympathetic amine, meaning that it causes effects similar to the rush of adrenaline experienced during the “fight or flight” response.

The primary effect of that response is vasoconstriction – the narrowing and tightening of blood vessels – in the digestive system, as well as vasodilation – the expansion of blood vessels – in the skeletal muscles, lungs, heart, and brain.

The simulated stress response causes chemical changes that get your heart beating faster to flood muscles with the oxygen and nutrients they need. This leaves some phentermine users reporting increased blood pressure and increased heart rate as a result of taking the medication.

The cardiovascular effects of taking phentermine are why it can be dangerous to use the drug if you have a history of high blood pressure and/or heart disease.

These effects can also help to explain phentermine headaches. Much like having too much caffeine causes headaches, so too can having too much phentermine. When the cerebral arteries dilate – as per the flight or fight response – more blood flows to the brain.

While brain tissue doesn’t feel any pain itself, an expansion of the blood vessels could cause the nerves to send a pain signal to your head and face. The signals could be the cause of your phentermine-induced headaches.

If you are taking a high dose of phentermine and your headaches – or any other side effects – don’t go away, you should talk with your doctor. They may want to reduce your dose. You should never change your dose or schedule without consulting your doctor first.

Dehydration

Dehydration is another common cause of phentermine headaches. Your doctor may have mentioned to you that you should drink a lot of water while taking phentermine. Getting water and staying hydrated is important for kidney health, controlling cravings, and keeping skin healthy.

Being hydrated also helps to manage other common phentermine symptoms like dry mouth (xerostomia). While this isn’t caused by dehydration itself, not getting enough water certainly makes xerostomia worse.

With the high fluid requirements that come with taking phentermine, it’s all too easy to become dehydrated. Whether you’re taking phentermine or not, there’s no denying that not getting enough water causes headaches. Dehydration makes tissue and blood vessels contract, and it causes electrolyte imbalances. These can trigger pain signals in the head. The trick to preventing – as well as treating – these headaches is to get enough fluids. Try to drink enough water to keep pee a light yellow color and keep tissues hydrated.

If you can feel a headache coming on, drink a few glasses of water as soon as you can. If the headache is caused by dehydration, then drinking 2 or 3 glasses of water should provide some relief within 30 minutes to 3 hours. Keep in mind that alcoholic and caffeinated beverages serve to make you even more dehydrated, so choose something that is free from sugar and caffeine if you want to be hydrated.

Skipping Meals

Skipping meals is another common cause of phentermine headaches, as is just not eating enough. Following restrictive diets can cause headaches as a result of low blood sugar, stress hormones, or a combination thereof.

Our cells need glucose (blood sugar) for energy. Outside of bodily cells, neurons also consume a lot of glucose. Getting enough glucose is vital to ensuring your brain is working at full capacity. It therefore makes sense that a headache is one of the first signs of low blood sugar.

Low blood sugar, also known as hypoglycaemia, can lead to headaches, nausea, confusion, and other symptoms. The risk of developing a glucose-related headache is increased for those with diabetes, those who fast, and those who consume a high-sugar diet.

Your body will also release stress hormones during fasting, which can cause – or exacerbate – headaches for some people.

You can minimize the risk of developing a hypoglycemic headache by eating every four to six hours while awake. If you have trouble regulating blood sugar, or just have diabetes itself, then you may want to try getting a meal or snack every 3 – 4 hours.

When you find yourself too busy to have a proper meal, you should try to eat a healthy snack or a meal replacement you can have on the go. When it comes to calorie intake, women should aim to get around 1,200 and men should aim for 1,500 calories per day when taking phentermine to support proper biological function.

Lack of Sleep

Finally, not getting enough sleep can cause headaches (or migraines) for most people. Insomnia is one of the side effects of phentermine, making it a common cause for phentermine headaches too. Getting too much sleep, too little sleep, or fractured sleep can cause and exacerbate headaches.

Sleeping troubles contribute to head pain as the brain uses sleep as a time to refuel and recharge. If you don’t give your brain the rest that it needs, it can cause headaches. The pain could present as a tension-type headache or as a migraine.

You can prevent this by getting between 7 and 9 hours sleep each night. If you are being kept up by phentermine, then try taking your dose early in the morning. That way, the medication has plenty of time to pass through your system and wear off before you go to bed.

How to Get Rid of a Phentermine Headache

We’ve looked at all the common causes of phentermine headaches but, no matter what is causing the headache, you are likely interested in how to stop it. Like many of the side effects of phentermine, phentermine headaches are likely to diminish or disappear when you adjust to the medication. Still, there are some things you can do to mitigate your headache in the meantime.

Prevent Triggers

The first thing you want to do is prevent headache triggers in the first place. Whether it’s skipping breakfast, having a coffee in the afternoon, or not getting enough water – try to identify the causes of your phentermine headaches and then avoid them in future. Preventing headaches is the easiest way to deal with them.

Use Painkillers

If the headache isn’t too bad then you could treat it with an over-the-counter (OTC) painkiller such as Advil or Tylenol. Make sure that you take the pills with plenty of water and avoid taking more than the recommended dose.

Consult Your Doctor

Lastly but most importantly, if the headaches absolutely won’t go away, or they become severe, then you should consult your doctor as soon as possible. A headache that’s on the level of the worst you’ve ever head could be a sign of a serious medical problem. You should get it checked out as soon as possible. Similarly, headaches that won’t go away or interfere with your daily life are something that a prescribing doctor should be told about.

Last updated: Jan 13, 2023. Bookmark the permalink.

What should you do if you have headache with Phentermine?

by Rakib Sarwar, RPh

Published on March 6, 2019 and last updated for accuracy on September 19, 2022

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With so many people battling with overweight and obesity-related problems, new weight loss drugs cannot stop hitting the market anytime soon. With several new weight loss drugs being advertised by different companies, one needs to be careful when choosing. You don’t want to spend your hard-earned money on drugs that can neither help you lose weight nor maintain your normal health.

The worldwide popularity of phentermine may be related to its effectiveness for weight loss. In this post, we will help you learn about phentermine, who can take it, side effects to watch out for, and phentermine may cause headaches (1).

What is phentermine?

Phentermine is an over-the-counter drug for weight loss. It can come in different forms such as an oral capsule, orally disintegrating tablet, or an oral tablet. Phentermine capsule comes as the Adipex-P drug brand. It can also come in the form of a generic drug.

All generic drugs are known to be more affordable than their branded counterparts. In most cases, these generic versions may not come with the strength and form the branded ones come in. Since phentermine is a form of controlled substance, it is important you ensure the close monitoring of a doctor while you are on this drug (6).

Potential risks of phentermine use

The oral capsule form of phentermine is administered for some weeks as a treatment for obesity. This is one drug that has been found to help obese and overweight people lose weight. However, it comes with some known health risk issues (2).

Some common risk factors associated with the use of phentermine include high cholesterol, high blood pressure, and diabetes. Phentermine is used alongside weight loss exercises, a low-calorie diet plan, and some behavioral changes aimed at enhancing your weight loss (5).

How phentermine may help you lose weight

Phentermine is a member of the anorectics drug class. A drug class is made up of a group of medications formulated to work in the same way. Drugs belonging in the same class are used for the treatment of similar cases (2).

It is believed that phentermine helps you lose weight by enhancing the production of important brain chemicals that help curb your appetite. The release of these brain chemicals can help curb your food cravings, thereby aiding your weight loss faster (3).

Phentermine and headaches – a common complaint

Headaches (including migraines) are among the most commonly experienced side effects while on phentermine. These headaches can range from mild to severe (4).

These headaches may or may not be related to the phentermine pills. The lifestyle changes you initiate while on phentermine can account for the recurrent headaches you experience. Whether these headaches are mild or severe, they are known to affect your overall comfort and quality of life.

Below, we will help you learn the most possible causes of a headache while on phentermine and how you can overcome this side effect. Most times these headaches would go away on their own, but if they persist, you may have to consult a physician as they may be a sign of an underlying serious ailment (4).

So who can get these headaches while taking phentermine?

Despite the fact that headache is a common side effect with phentermine, not everyone will experience it while taking phentermine. The people most prone to developing headaches while on phentermine are new users. Using phentermine alongside other drugs can also increase your chances of developing headaches with the drug (8). So, let’s see who stands a higher risk of developing headaches while on phentermine:

New Users

You stand a higher risk of developing headaches with phentermine as a new user. This is also applicable to most other common side effects that accompany the use of this weight loss drug (8).

The reason for this increased risk of developing headaches as a new user is related to the fact that your body needs some time before it can get used to the drug and its effects on your body (7).

Some people are known to be more sensitive to chemical substances than others. So, if you are among the overly sensitive type, you will most likely react more to phentermine and experience more of these headaches than most other new users would. These headaches are part of your body’s way of adjusting to the new drug and its effects (8).

However, if this headache persists for more than a few days or weeks, you may need to get in touch with your doctor to help diagnose any underlying ailment. Where there is no underlying ailment, your doctor may decide to change your phentermine dosage or change the schedule to help you experience fewer side effects (4).

Most times, it is not about taking a high dose of the drug as phentermine still produces the needed weight loss effects even at a lower dosage. However, make sure you never change your schedule or dosage without speaking with a doctor first (7).

Smokers and drinkers

One other major factor that increases your risk of developing headaches with phentermine is your lifestyle changes and choices while on phentermine. The drug interaction between phentermine and chemical substances is one reason why you would experience more headaches while drinking, smoking or taking caffeine alongside phentermine. This is why it is advised you avoid taking these substances while on phentermine (9).

It is advised you never combine alcohol and phentermine as it can be one dangerous combination that can usher in loads of side effects. The interaction of alcohol with phentermine is known to increase stress, dizziness, and sleepiness in your body. This interaction can also increase your blood pressure. So, make sure you skip alcohol whenever you are on phentermine to curb these side effects (10).

Also, nicotine and caffeine are two other intoxicating substances you may wish to never combine with phentermine. These are stimulants and can lead to higher risks of side effects with phentermine. A severe headache is a common side effect that occurs when you combine phentermine with any of these stimulants (10).

So what are some possible causes of headaches while on phentermine?

There are several possible causes of headaches with phentermine just like we have mentioned earlier. Sometimes, it is difficult to identify the real cause of each an individual headache while taking phentermine.

Therefore, knowing the possible causes of headaches while on phentermine will go a long way to help you identify the major cause you should deal with at any particular time. Below are some common possible causes of headaches while on phentermine. Some of these causes may be related to the drug itself or some lifestyle changes that accompany the drug intake.

1. Taking additional stimulant drugs or supplements

The stimulant effects have been identified as one major possible cause of headaches while on phentermine. Phentermine creates certain effects in your body that can be likened to the adrenaline rush termed the “flight or fight” response. One major effect of this adrenaline rush-like response is the narrowing and tightening of your blood vessels in your body’s digestive organs. Another effect this response can have in your body is the widening of the blood vessels in your brain, lungs, heart, and skeletal muscles (9).

Most of these chemical changes that come with this type of stimulated stress response can increase your heartbeat. And this increased heartbeat supplies the needed nutrients and oxygen to your body. This is why most phentermine takers would always report an increase in their heart rate and blood pressure while on the drug. These cardio changes are the major reasons why taking phentermine with a history of high blood pressure or any heart diseases is considered dangerous (9).

The synthesized stress response initiated by the dilation of the cerebral arteries increases the flow of blood to your brain. While this may not cause any brain pains, the expansion of your blood vessels can trigger the surrounding nerves which send pain signals to your face and head. These pain signals may be the major reasons why you experience headaches with phentermine (9).

If you experience persistent headaches with a high dose of phentermine, you may wish to ensure you speak with your doctor to reduce your dosage and change your schedule.

2. Dehydration

Dehydration is one other major cause of headaches with phentermine. Most doctors will advise you to take plenty of water while taking phentermine. Staying adequately hydrated will help you keep your kidneys protected, control your food cravings, and nourish your skins. It will also help you control the common side of effect of phentermine known as xerostomia or dry mouth. While this xerostomia may not be caused by dehydration, not taking enough water can worsen the condition (9, 11).

It is easy to become dehydrated when you forget to take enough fluids. It is a known fact that not taking enough water can give you headaches even when you are not on phentermine. Being dehydrated will make your blood vessels to contract, keep your electrolytes unbalanced, and these two effects of dehydration can lead to severe pain signals in your brain (9, 11).

So, taking adequate fluids is one way you can treat this type of headache. Make sure you consume enough water to keep your body tissues adequately hydrated. Taking 2-3 glasses of water when you experience a sudden headache will help you keep the headache at bay. If your headache is caused by dehydration, it should go away from 30 minutes to 3 hours (9, 11).

Never forget you stand the risk of becoming more dehydrated with alcoholic and caffeinated beverages. The best drinks to help you stay hydrated are sugar-free, caffeine-free drinks (11).

3. Skipping Meals

Skipping meals is one other major reason why you will likely develop headache with phentermine. Not eating enough food can also make you develop a headache while on phentermine. Following a highly restrictive diet can also leave you with headaches due to the low blood sugar associated with such restrictive diets (9, 11).

Your body cells make use of glucose known as blood sugar for energy. Among your body cells, your body neurons consume most of the glucose. So, to ensure your brain keeps functioning at a high peak, make sure you control your body’s glucose supply. This explains why any drop in your body’s blood sugar gives you headaches. Once you develop low blood sugar or hypoglycemia, you can have headaches, nausea, confusion, or any other symptoms. If you have diabetes, fast for long, or eat foods high in sugar, you will experience more glucose deficiency-related headaches (9, 11).

Your body will also release stress hormones whenever you fast, and these stress hormones can worsen your headaches when on phentermine. To keep your hypoglycemic headaches away, eat once in every 4-6 hours. If you have a problem controlling your blood sugar or any diabetes-related complications, you can settle for meals or snacks every 3-4 hours while you are awake (10, 11).

If you are too busy to eat regularly, make sure you complement with a good meal replacement shake or some healthy snack. You can limit your calorie intake to about 1200 each day as a woman or 1500 a day as a man while on phentermine (10, 11). This will help regulate and maintain important healthy bodily functions. Additionally, taking adequate meals while on any drugs helps the drug function more effectively.

4. Inadequate Sleep

Last but not the least on the list of possible causes of headaches while on phentermine is lack of sleep. Insomnia has been identified as one common side effect that accompanies phentermine intake. Getting more sleep than you need, not getting enough sleep and frequent sleep disruption can worsen your headaches while on phentermine (12).

Your brain relies on these sleep hours to refuel and recharge. Any type of sleep problems will deny your brain this much-needed adequate rest, and the end result could be a severe headache. To keep this headache trigger at bay, make sure you get about 9 hours sleep every night (9, 12). If phentermine interferes with your night sleep, you can take it first thing in the morning. Taking the drug early enough may help ensure its effects wear off before your bedtime (12).

How to get rid of headache while on phentermine

We have seen some of the possible causes of headaches while on phentermine. However, it is important we mention some ways you can get rid of headaches irrespective of the cause. Most phentermine side effects are known to vanish own their own as your body becomes accustomed to the effects of the drug (5). Here are some possible ways you can get rid of headache while on phentermine:

1.

Do all you can to keep triggers away

The first step to keeping away headaches while taking phentermine is to prevent as many triggers as possible. Once you identify common triggers such as not taking enough water, skipping meals, or taking stimulants, do all you can to avoid them. Preventing headache remains the most effective way of dealing with it (9).

2. Take a painkiller

You can treat minor headaches with some over-the-counter painkillers. However, it is important you stick with the recommended dosage and ensure you take the painkiller with adequate water (9).

3. Consult your doctor

If the headache refuses to go away or becomes severe, try to get medical help as soon as possible. A severe headache can be a sign of an underlying medical condition and can be diagnosed by a physician. Also, any headaches that refused to go away after taking a painkiller is something your doctor should attend to as soon as possible (9).

Once you take these steps, you can enjoy your phentermine and all of its weight loss benefits without experiencing any discomforting headaches and head pains.