Methamphetamine (Oral)

Methamphetamine is a controlled drug used to manage the symptoms of ADHD, and to aid weight loss in obese people who have not had success with other treatments.


Methamphetamine is a central nervous system (CNS) stimulant most commonly used to treat ADHD. It affects various chemicals in the brain which cause hyperactivity and impulse control, and can therefore reduce restlessness and improve focus and concentration. It is prescribed to both adults and children, and tends to be used alongside a comprehensive treatment plan which involves psychological, social, and educational intervention.

Sometimes methamphetamine is also used to treat obesity in people who have struggled to adhere to a diet or not had success with other weight loss treatments. The drug reduces appetite, but it must be used alongside a doctor-approved, calorie-controlled diet in order to be successful. It tends to be reserved for people who are significantly overweight and have secondary health problems as a result of their obesity.

In the US, oral methamphetamine is known by the brand name Desoxyn and it is only available with a doctor's prescription. Since methamphetamine is a habit-forming drug, it is strictly controlled. Prescriptions cannot be refilled, and instead patients must obtain a new prescription each time they require more medicine. The drug is administered orally and is provided in tablet form.

Conditions Treated?

Type Of Medicine?

  • CNS stimulant

Side Effects

Sometimes methamphetamine can cause a variety of unwanted effects as well as its needed effects. While it is unlikely that all of these symptoms will occur, patients need to be aware of them in order that they can recognize the need to seek medical attention.

The following side effects are serious and should be reported to a doctor immediately:

  • False or unusual sense of well-being
  • Unusual tiredness or weakness
  • Trouble sleeping
  • Agitation
  • Restlessness
  • Delusions
  • Hallucinations
  • Dizziness
  • Faintness
  • Blurred vision
  • Chest pain or discomfort
  • Difficulty breathing
  • Rapid, pounding or irregular heartbeat or pulse
  • Pounding in the ears
  • Uncontrollable vocal outbursts or tics
  • Uncontrollable twitching, twisting, or repetitive movements of the tongue, lips, face, arms, or legs
  • Muscle spasms or cramps
  • Muscle pain or stiffness
  • Trembling of hands or feet
  • Shakiness in arms, hands, legs, or feet
  • Swelling of feet or lower legs
  • Headache
  • Fever

The following side effects associated with methamphetamine are less serious and only require medical attention if they become very severe, persistent, or bothersome. Consult your doctor if you have questions about them.

  • Unpleasant or unusual taste in mouth
  • Change in taste
  • Dry mouth
  • Indigestion
  • Passing of gas
  • Itching
  • Skin rash
  • Redness of the skin
  • Hives or welts
  • Constipation
  • Unexplained weight loss
  • Decreased sex drive or sexual ability
  • Inability to achieve or maintain an erection

These may not necessarily be exhaustive lists of all side effects which could occur during treatment with methamphetamine. If you notice others not listed here, consult your doctor as soon as possible. You could also report new side effects to the FDA, or your doctor may want to do this on your behalf.


The amount of methamphetamine a patient takes depends on many different factors, including the patient's medical history and the condition being treated. It is not uncommon for dosages to gradually increase over time, particularly when the drug is used for ADHD, if lower dosages do not have the desired effect.

For ADHD, most adults and children aged 6 years and older begin with 5mg of methamphetamine taken once or twice each day. The dose is then increased as necessary over a number of weeks. For children under the age of 6 years, the use and dose of methamphetamine should be determined by a doctor.

For weight loss, adults and children aged 12 years and older usually take 5mg of methamphetamine 30 minutes before each main meal. The drug is not recommended for aiding weight loss in children under 12.

Methamphetamine can be habit-forming. It is vital that patients do not take more of the drug than is prescribed to them, or more frequently than instructed. Doing so could increase the risk of physical dependency. If you feel that the medicine is not providing the effects that you hoped for, consult your doctor and only increase your dose under their instruction.

Since methamphetamine stimulates the central nervous system, it can prevent sleepiness when taken late in the evening. Avoid late dosages to ensure your sleep is not disturbed.


There are a variety of medicines which can interact with methamphetamine and cause harmful effects. It is vital that you tell your doctor about all the medicines you take, including those purchased over the counter, those prescribed to you, and any herbal supplements or vitamins.

It is particularly important to mention the following types of medicines:

  • Monoamine oxidase (MOA) inhibitors (if taken within the past 14 days)
  • Antidepressants
  • Medicines for mental health conditions, including herbal remedies
  • Opioid medicines
  • Medicines for Parkinson's disease
  • Antiviral medicines
  • Antiemetics
  • Medicines for headaches and migraines

You should not start taking any new medicines without first checking with your doctor that it is safe to do so.

Your doctor will assess whether harmful interactions are likely and where necessary they may change some of the medicines you already take in order that you can take methamphetamine safely. If all medicines are deemed vital, your doctor may continue to prescribe them, but they may adjust your dosages or give you new instructions as to when to take your medicines. It is vital that you follow these instructions closely.

The following medicines should never be taken at the same time as methamphetamine. If you take any of them, your doctor will either find an alternative to methamphetamine, or they will change your existing medicines.

  • Brofaromine
  • Clorgyline
  • Furazolidone
  • Iproniazid
  • Isocarboxazid (Marplan)
  • Lazabemide
  • Linezolid (Zyvox)
  • Moclobemide (Manerix)
  • Nialamide
  • Pargyline
  • Phenelzine (Nardil)
  • Procarbazine (Matulane)
  • Rasagiline (Azilect)
  • Selegiline (Eldepryl, Zelapar)
  • Toloxatone
  • Tranylcypromine (Parnate)

The following medicines are not recommended for use at the same time as methamphetamine, but they may still be administered together if both are deemed important. Your doctor may instead change your dosages or the way in which you take them.

  • Donepezil (Aricept)

The following medicines can increase the risk of certain side effects when taken at the same time as methamphetamine. If both medicines are deemed important, your doctor may change your dosages or the way in which you take them.

  • Ritonavir (Norvir)


Contraindicated medical conditions

Patients with the following medical conditions should not use methamphetamine due to a risk of dangerous complications:

Risk of worsening medical conditions

The use of methamphetamine in patients with the following health conditions may be dangerous, as the drug could make the conditions worse. However, if the benefits of the drug far outweigh potential risks, doctors may continue to prescribe it. They may request closer monitoring of the patient, or they may administer lower doses initially.

Risk of dependency

Methamphetamine is a habit-forming drug, particularly when taken in high doses and for long periods of time. Patients with a history of drug abuse or addiction may not be able to take methamphetamine.

To minimize the risk of dependency, patients should only take their prescribed dosages and should not take it more frequently or for longer than instructed by their doctor. When treatment ends, doctors may gradually taper off dosages to minimize the risk of physical withdrawal effects.

If you notice the following signs of dependency, consult your doctor immediately:

  • Strong desire to keep taking the medicine
  • A need to increase the dose to achieve the same effects

When tapering off methamphetamine, you may notice the following withdrawal effects. If they are difficult to cope with, consult your doctor, as it may be possible to taper off the medicine at a slower rate.

  • Mental depression
  • Trembling
  • Unusual tiredness or weakness
  • Stomach pain or cramps
  • Nausea or vomiting

Risk of heart, blood vessel, and circulation problems

Sometimes methamphetamine can cause serious heart or blood vessel problems, or a disease called the Raynaud phenomenon which affects blood circulation in the fingers and toes. These risks are heightened in people with a history of heart or blood vessel disease or Raynaud disease. If you experience any of the following symptoms, consult your doctor straight away:

  • Chest pain
  • Labored breathing
  • Fainting
  • Tingling, pain, or cold feeling in fingers and toes
  • Paleness or skin color changes in fingers and toes
  • Unexplained sores or ulcers on fingers and toes

Risks to mental health

Methamphetamine may cause new or worsening depression, anxiety, agitation, or psychosis. The risk of this occurring is higher in people with a history or family history of mental health problems. Make sure your doctor knows about your mental health history in order that they can assess whether the drug is safe for you.

If you or people around you notice changes in your behavior, consult your doctor straight away. Examples of changing behavior including:

  • Aggression
  • Hostility
  • Agitation
  • Irritability
  • Depression
  • Paranoia or delusions
  • Hallucinations
  • Unusual thoughts

Risk of dizziness

Methamphetamine can cause dizziness, lightheadedness, or drowsiness. Do not operate machinery, drive, or perform any other activities that require you to be alert until you know how the drug affects you.

Keep all appointments

Your doctor will want to see you on a regular basis during treatment with methamphetamine to assess how well the drug is working and check for adverse effects. It is very important to keep all your appointments and to undergo all tests requested by your doctor.

You should also note that methamphetamine can affect the results of certain medical tests. Be sure to tell any doctor that requests medical tests that you are taking this drug.

Pediatric use

Methamphetamine is not approved for use in children under six for the treatment of ADHD. It is also not suitable for children under 12 years for the treatment of obesity.

Methamphetamine may result in slow growth when taken by children. Doctors will periodically assess the child's height and weight to check for this adverse effect.

Geriatric use

It appears that methamphetamine is just as effective in treating elderly patients as it in treating younger adults. However, elderly patients are more likely to have age-related heart problems, which could make them more susceptible to serious side effects affecting the heart, blood vessels, or circulation. Doctors may therefore be more cautious in prescribing the drug to this population.

Pregnancy and breastfeeding

Animal studies have demonstrated that methamphetamine could be harmful to the fetus when taken during pregnancy. There are few controlled studies in humans into these effects. For this reason, use of the drug is not recommended during pregnancy unless the benefits of the drug far outweigh potential risks of fetal harm. If you become pregnant while taking methamphetamine, consult your doctor straight away.

Methamphetamine is excreted in breast milk, but there have not been adequate studies into the effects of the drug on nursing infants. Breastfeeding is therefore not recommended during treatment with methamphetamine. If patients stop taking methamphetamine in order to breastfeed, they should wait 24 to 48 after their last dose until they breastfeed.


Do not take methamphetamine if you have had an allergic reaction to the drug in the past, or to drugs like it. Tell your doctor about all the allergies you suffer from, including drug, chemical, dye, food, and animal allergies, so that they can check that you are not allergic to any of the ingredients in methamphetamine.

If you notice any of the following signs of allergic reaction while taking methamphetamine, get emergency medical help:

  • Skin rash, hives, or itching
  • Difficulty breathing
  • Swelling of the face, lips, tongue, or throat


Methamphetamine should be stored in the container it was provided to you in with the lid tightly closed at all times when not in use. Keep it away from direct light, heat, and moisture, and store it at room temperature. Do not allow it to freeze.

Keep methamphetamine out of sight and reach of children at all times. Never share the medicine with other people, as it could be extremely dangerous for people who it is not prescribed to.

If you have unused or expired methamphetamine, do not keep it. Ask your healthcare provider how to dispose of it. Do not throw it down the trash or flush it down the toilet as it could come to harm other people. Use a medicine take-back program. This may be offered by your healthcare provider, a local pharmacy, or a garbage or recycling center.


Methamphetamine is used to treat ADHD and obesity. It stimulates the central nervous system (CNS), and can cause dependency when taken for long periods of time or in high doses. It can help to improve concentration and reduce restlessness in people with ADHD but is usually used in combination with other psychological interventions. When used to treat obesity, it is only suitable for very overweight patients who have not had success with other treatments or diets alone. It can help to reduce appetite when used in combination with a calorie-controlled diet.

Although methamphetamine can be prescribed to children, it is not suitable for children under six for treatment of ADHD, or children under 12 for treatment of obesity. The drug is not recommended for use during pregnancy and while breastfeeding.

Patients may experience indigestion, skin redness or mild skin rashes, constipation, weight loss, and changes in sex drive while taking methamphetamine. These are minor side effects and do not require medical attention. If patients experience changes in mood or behavior, breathing problems, chest pain, muscle spasms, seizures, or pounding heartbeat, they should consult their doctor immediately.