Phentermine
Risk Factor: CM
Class: CENTRAL NERVOUS SYSTEM DRUGS
/ Stimulants and/or Anorexiants
Contents of this page:
Fetal Risk Summary
Breast Feeding Summary
References
Questions and Answers
Fetal Risk Summary
Phentermine (phenyl-tertiary-butylamine) is a sympathomimetic amine that has activity as a central nervous system stimulant. Similar to other drugs in this class, such as the amphetamines, it is used as an appetite suppressant in the treatment of obesity. In addition to other adverse effects, hypertension has occurred in adults treated with this agent.
Reproduction studies in animals investigating if phentermine is teratogenic have not been conducted. A closely related compound, chlorphentermine (30 mg/kg/day SC), was administered to pregnant rats during the last 5 days of gestation (1). Phospholipidosis was evident in the lungs of the mothers and the newborn rats, and 83% of the latter died within 24 hours of birth. Another group treated with phentermine (30 mg/kg/day SC) in a similar manner did not develop the complication and did not die. A subsequent Reference suggested that the chlorphentermine-induced pup mortality was consistent with retardation of fetal pulmonary maturity (2).
No studies have been located that described the placental transfer of phentermine in animals or humans, but because of its low molecular weight (about 186), exposure of the fetus to the drug should be expected.
A study published in 1962 described the use of phentermine in 118 women who were treated for obesity during the 3rd trimester of pregnancy up to delivery (3). Women weighing less than 200 pounds were given 30 mg each morning, while those more than 200 pounds were given with 30 mg twice daily. The weights of the patients before treatment ranged from 180 to 315 pounds. Adverse outcomes occurred in five women with stillborn infants (three females and two males), one of whom was caused by abruptio placentae. The cause of the other stillborns, whose weights ranged from 9 to 10 pounds, was not mentioned, other than the statement that one mother had mild preeclampsia.
The FDA has received two reports involving the use of the combination fenfluramine and phentermine in early pregnancy (F. Rosa, personal communication, FDA, 1997). A spontaneous abortion occurred in one of the pregnancies. In the other, an infant with bilateral valvular abnormalities, both aortic and pulmonary, with moderate stenosis and displacement was delivered. Because valvular toxicity has been reported in adults taking the combination, a causal relationship in the pregnancy case is potentially possible. No other details of these cases were available.
That any real benefit is derived from the use of phentermine for weight control during pregnancy is doubtful, and its use during gestation, especially during the 1st trimester, should be considered contraindicated. Moreover, although the causes of the stillbirths in the human study cited above were not fully elucidated and may not have been caused by maternal treatment with phentermine, the high incidence is disturbing and is a reason to withhold use of the drug during pregnancy.
Breast Feeding Summary
No reports describing the use of phentermine during lactation have been located. Based on its low molecular weight (about 186), however, the excretion of phentermine into breast milk should be expected. Because central nervous system stimulation and other adverse reactions may occur in a nursing infant exposed to this drug in milk, breast feeding should be considered a contraindication if the mother is taking phentermine.
References
- Thoma-Laurie D, Walker ER, Reasor MJ. Neonatal toxicity in rats following in utero exposure to chlorphentermine or phentermine. Toxicology 1982;24:8594.
- Kacew S, Reasor MJ. Newborn response to cationic amphiphilic drugs. Fed Proc 1985;44:23232327.
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Sands RX. Obesity and pregnancy. Weight control with a resinate. Am J Obstet Gynecol 1962;83:161721.
Questions and Answers
Is it safe to take Adipex or phentermine while pregnant? What are the pros and cons? I am 8 weeks pregnant and was taking phentermine to control my weight, since I found out I was pregnant 4 weeks ago, I only take them about 3 times a week. I would like any facts on this medicine and safety during pregnancy. I am really scared to let my weight get out of control during pregnancy again and wondering how to cope with exhaustioin that I have if I dont take the pills. I would love to hear from anyone with personal experience or a member of the medical community...Thank you!!!
The answer is an absolute NO. Stop taking the drug, tell your MD about it and throw what you have left out so you won't be tempted. This drug is a controlled amphetamine. The safety of this drug while used during pregnancy has not been established and has the potential to cause still birth. I understand your concern about weight gain during pregnancy but it can be controlled. Ask your OB/GYN about diet and exercise while pregnant, he or she can give you the answers you need. First and foremost put the safety of your unborn child first. The right combination of diet, exercise and vitamins should also help the energy level. Good luck and stay healthy.
Will taking Phentermine affect anything as far as getting pregnant? I am going to start taking Phentermine. Im not overweight just going to get some extra weight off before I get pregnant. I know it sounds goofy but I gain so much weight being pregnant. Im only doing it for two months since my hubby and I are probably going to start trying in June. Any comments?
Hey.......you just want to be sure to wait at least 6 weeks before you start trying to have a baby to make sure all that phentermine is out of your system or else it could make your baby have birth defects if it is still in your system when you have concieved.
is it illegal to use phentermine while pregnant?
It's illegal to use phentermine in most states in the US period. It could potentially harm the baby if you are taking it during pregnancy. It's not safe to take for you or the baby. Phentermine has been known to cause heart problems later down the line, but for the baby, it could cause abnormalities or even death. Speak to your doctor. If you want to lose weight, wait until the baby is born. In the meantime, try walking to get some exercise and slow down the weight gain.
Can you take Phentermine if your pregnant?
NOOOO... Dont even try it... It can hurt the baby.
is phentermine safe to use during pregnancy? Has anyone else used phentermine while pregnant? Is there any new research out? All the old research claims no effect??
I wouldn't take anything, remember the drug Thalidomide,they did all the research on that one and looked what happened.For most woman an additional 200 cal per day is all that's required. Try juicing it's a great way to increase your intake of nutrients whilst controlling your calorie count,also eat food high in folic acid. Carrot's,Lettuce and Cantaloupe.
I just found out I'm pregnant, but I've been taking phentermine for 2 months. What will happen to my baby? Will my child have serious issues
Your baby is most likely just fine. How far along are you? The early the pregnancy the better off the baby is. I would stop taking it and talk to your OB about it.
i just found out that I am 10weeks pregnant and have been taking phentermine? Stoped taking. How dangerous?
please go to a doctor and have your baby checked out please
I have been taking phentermine, and I just found out that I am pregnant. Will my baby be ok? I will not take it again of course. I just took a test and it came up positive. I am probably only two or three weeks. I had my last period, and was supposed to start this one in one or two days. If I took phentermine in the very beginning, should my baby be ok? Also, last weekend I drank some alcohol (which I hardly ever do). Is there a huge risk to my baby because I drank? I didnt know I was pregnant yet, or I never would have....
I think a lot of people drink and take medications before they realize that they are pregnant. I stopped taking mine the day I found out. I would just talk to your dr about it.
Question for anyone in the medical field about pregnancy and Phentermine? I started taking Phenetermine to lose weight about a week and a half ago. Well yesterday, I just found out that I am 5 wks pregnant. Does anyone know what this can do to my baby? Im afraid to tell my regular Dr b/c she is going to rip my head off but I honestly had no idea!
You need urgently to consult your doctor and confide in your husband whatever the outcome can be, read this
Obesity is the main problem during pregnancy and may lead to diabetes in pregnant women. As per the latest survey carried out by the various research teams, there are no side effects of Phentermine in case of pregnant women if it is taken as per prescribed doses.
But if the doses of Phentermine are consumed in large quantity, there is a risk of abnormal development of fetus, so to reduce these risks, prescribed doses needs to be followed in proper manner under strict vigilance of the doctor. But it is an advice to the pregnant women that they should avoid Phentermine during pregnancy period because it may lead to gestational diabetes. Sometimes Phentermine can cause various withdrawal symptoms in case of pregnant women. To avoid all these side effects, Phentermine should be stopped before start of pregnancy stage and doctor needs to be consulted for more information about Phentermine
http://ezinearticles.com/?Phentermine-an...
There is a forum of Phentermine users that discuss this problem
http://www.phentermine.com/forums/ultima... (This is a forum run by the manufacturers of this medication so take their advice very cautiously).
